ETH Price: $2,526.42 (+1.25%)

Transaction Decoder

Block:
21750688 at Feb-01-2025 09:11:11 AM +UTC
Transaction Fee:
0.001563200773912357 ETH $3.95
Gas Used:
412,361 Gas / 3.790855037 Gwei

Emitted Events:

229 FiatTokenProxy.0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef( 0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef, 0x000000000000000000000000d127643c855aa9baef66ab895049aa0264a74453, 0x0000000000000000000000002b3f201543adf73160ba42e1a5b7750024f30420, 000000000000000000000000000000000000000000000000000000012a05f200 )
230 L1ChugSplashProxy.0x718594027abd4eaed59f95162563e0cc6d0e8d5b86b1c7be8b1b0ac3343d0396( 0x718594027abd4eaed59f95162563e0cc6d0e8d5b86b1c7be8b1b0ac3343d0396, 0x000000000000000000000000a0b86991c6218b36c1d19d4a2e9eb0ce3606eb48, 0x000000000000000000000000b62f35b9546a908d11c5803ecbba735abc3e3eae, 0x000000000000000000000000d127643c855aa9baef66ab895049aa0264a74453, 000000000000000000000000d127643c855aa9baef66ab895049aa0264a74453, 000000000000000000000000000000000000000000000000000000012a05f200, 0000000000000000000000000000000000000000000000000000000000000060, 000000000000000000000000000000000000000000000000000000000000000b, 7375706572627269646765000000000000000000000000000000000000000000 )
231 L1ChugSplashProxy.0x7ff126db8024424bbfd9826e8ab82ff59136289ea440b04b39a0df1b03b9cabf( 0x7ff126db8024424bbfd9826e8ab82ff59136289ea440b04b39a0df1b03b9cabf, 0x000000000000000000000000a0b86991c6218b36c1d19d4a2e9eb0ce3606eb48, 0x000000000000000000000000b62f35b9546a908d11c5803ecbba735abc3e3eae, 0x000000000000000000000000d127643c855aa9baef66ab895049aa0264a74453, 000000000000000000000000d127643c855aa9baef66ab895049aa0264a74453, 000000000000000000000000000000000000000000000000000000012a05f200, 0000000000000000000000000000000000000000000000000000000000000060, 000000000000000000000000000000000000000000000000000000000000000b, 7375706572627269646765000000000000000000000000000000000000000000 )
232 Proxy.0xb3813568d9991fc951961fcb4c784893574240a28925604d09fc577c55bb7c32( 0xb3813568d9991fc951961fcb4c784893574240a28925604d09fc577c55bb7c32, 0x000000000000000000000000091ce9f7a74ab776b69d3f0dc5c08c39b3a0cb2a, 0x0000000000000000000000004200000000000000000000000000000000000007, 0x0000000000000000000000000000000000000000000000000000000000000000, 0000000000000000000000000000000000000000000000000000000000000020, 000000000000000000000000000000000000000000000000000000000000024d, 0000000000000000000000000000000000000000000000000000000000000000, 0000000000000000000000000000000000000000000000000000000000000000, 000000000007832e00d764ad0b00010000000000000000000000000000000000, 00000000000000000000002fe10000000000000000000000002b3f201543adf7, 3160ba42e1a5b7750024f3042000000000000000000000000042000000000000, 0000000000000000000000001000000000000000000000000000000000000000, 0000000000000000000000000000000000000000000000000000000000000000, 00000000000000000000030d4000000000000000000000000000000000000000, 000000000000000000000000c000000000000000000000000000000000000000, 000000000000000000000001040166a07a000000000000000000000000b62f35, b9546a908d11c5803ecbba735abc3e3eae000000000000000000000000a0b869, 91c6218b36c1d19d4a2e9eb0ce3606eb48000000000000000000000000d12764, 3c855aa9baef66ab895049aa0264a74453000000000000000000000000d12764, 3c855aa9baef66ab895049aa0264a74453000000000000000000000000000000, 000000000000000000000000012a05f200000000000000000000000000000000, 00000000000000000000000000000000c0000000000000000000000000000000, 000000000000000000000000000000000b737570657262726964676500000000, 0000000000000000000000000000000000000000000000000000000000000000, 0000000000000000000000000000000000000000000000000000000000000000 )
233 ResolvedDelegateProxy.0xcb0f7ffd78f9aee47a248fae8db181db6eee833039123e026dcbff529522e52a( 0xcb0f7ffd78f9aee47a248fae8db181db6eee833039123e026dcbff529522e52a, 0x0000000000000000000000004200000000000000000000000000000000000010, 0000000000000000000000002b3f201543adf73160ba42e1a5b7750024f30420, 0000000000000000000000000000000000000000000000000000000000000080, 0001000000000000000000000000000000000000000000000000000000002fe1, 0000000000000000000000000000000000000000000000000000000000030d40, 0000000000000000000000000000000000000000000000000000000000000104, 0166a07a000000000000000000000000b62f35b9546a908d11c5803ecbba735a, bc3e3eae000000000000000000000000a0b86991c6218b36c1d19d4a2e9eb0ce, 3606eb48000000000000000000000000d127643c855aa9baef66ab895049aa02, 64a74453000000000000000000000000d127643c855aa9baef66ab895049aa02, 64a7445300000000000000000000000000000000000000000000000000000001, 2a05f20000000000000000000000000000000000000000000000000000000000, 000000c000000000000000000000000000000000000000000000000000000000, 0000000b73757065726272696467650000000000000000000000000000000000, 0000000000000000000000000000000000000000000000000000000000000000 )
234 ResolvedDelegateProxy.0x8ebb2ec2465bdb2a06a66fc37a0963af8a2a6a1479d81d56fdb8cbb98096d546( 0x8ebb2ec2465bdb2a06a66fc37a0963af8a2a6a1479d81d56fdb8cbb98096d546, 0x0000000000000000000000002b3f201543adf73160ba42e1a5b7750024f30420, 0000000000000000000000000000000000000000000000000000000000000000 )

Account State Difference:

  Address   Before After State Difference Code
0x2b3F2015...024F30420
0x59625d1F...9b3471781
(beaverbuild)
12.372251291160368077 Eth12.373076013160368077 Eth0.000824722
0xA0b86991...E3606eB48
0xD127643c...264a74453
357.356043265227180697 Eth
Nonce: 971
357.35448006445326834 Eth
Nonce: 972
0.001563200773912357
0xf80be9f7...9b3A0bA19

Execution Trace

L1ChugSplashProxy.838b2520( )
  • ProxyAdmin.STATICCALL( )
  • L1StandardBridge.depositERC20To( _l1Token=0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48, _l2Token=0xb62F35B9546A908d11c5803ecBBA735AbC3E3eaE, _to=0xD127643c855aA9BAEf66ab895049AA0264a74453, _amount=5000000000, _minGasLimit=200000, _extraData=0x7375706572627269646765 )
    • FiatTokenProxy.01ffc9a7( )
      • FiatTokenV2_2.01ffc9a7( )
      • FiatTokenProxy.01ffc9a7( )
        • FiatTokenV2_2.01ffc9a7( )
        • FiatTokenProxy.23b872dd( )
          • FiatTokenV2_2.transferFrom( from=0xD127643c855aA9BAEf66ab895049AA0264a74453, to=0x2b3F201543adF73160bA42E1a5b7750024F30420, value=5000000000 ) => ( True )
          • ResolvedDelegateProxy.3dbb202b( )
            • AddressManager.getAddress( _name=OVM_L1CrossDomainMessenger ) => ( 0x958487e21ba9E073836d598E31f749726f23413f )
            • L1CrossDomainMessenger.sendMessage( _target=0x4200000000000000000000000000000000000010, _message=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minGasLimit=200000 )
              • Proxy.e9e05c42( )
                • OptimismPortal.depositTransaction( _to=0x4200000000000000000000000000000000000007, _value=0, _gasLimit=492334, _isCreation=False, _data=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
                  • Proxy.STATICCALL( )
                    File 1 of 11: L1ChugSplashProxy
                    // SPDX-License-Identifier: MIT
                    pragma solidity 0.8.15;
                    /**
                     * @title IL1ChugSplashDeployer
                     */
                    interface IL1ChugSplashDeployer {
                        function isUpgrading() external view returns (bool);
                    }
                    /**
                     * @custom:legacy
                     * @title L1ChugSplashProxy
                     * @notice Basic ChugSplash proxy contract for L1. Very close to being a normal proxy but has added
                     *         functions `setCode` and `setStorage` for changing the code or storage of the contract.
                     *
                     *         Note for future developers: do NOT make anything in this contract 'public' unless you
                     *         know what you're doing. Anything public can potentially have a function signature that
                     *         conflicts with a signature attached to the implementation contract. Public functions
                     *         SHOULD always have the `proxyCallIfNotOwner` modifier unless there's some *really* good
                     *         reason not to have that modifier. And there almost certainly is not a good reason to not
                     *         have that modifier. Beware!
                     */
                    contract L1ChugSplashProxy {
                        /**
                         * @notice "Magic" prefix. When prepended to some arbitrary bytecode and used to create a
                         *         contract, the appended bytecode will be deployed as given.
                         */
                        bytes13 internal constant DEPLOY_CODE_PREFIX = 0x600D380380600D6000396000f3;
                        /**
                         * @notice bytes32(uint256(keccak256('eip1967.proxy.implementation')) - 1)
                         */
                        bytes32 internal constant IMPLEMENTATION_KEY =
                            0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;
                        /**
                         * @notice bytes32(uint256(keccak256('eip1967.proxy.admin')) - 1)
                         */
                        bytes32 internal constant OWNER_KEY =
                            0xb53127684a568b3173ae13b9f8a6016e243e63b6e8ee1178d6a717850b5d6103;
                        /**
                         * @notice Blocks a function from being called when the parent signals that the system should
                         *         be paused via an isUpgrading function.
                         */
                        modifier onlyWhenNotPaused() {
                            address owner = _getOwner();
                            // We do a low-level call because there's no guarantee that the owner actually *is* an
                            // L1ChugSplashDeployer contract and Solidity will throw errors if we do a normal call and
                            // it turns out that it isn't the right type of contract.
                            (bool success, bytes memory returndata) = owner.staticcall(
                                abi.encodeWithSelector(IL1ChugSplashDeployer.isUpgrading.selector)
                            );
                            // If the call was unsuccessful then we assume that there's no "isUpgrading" method and we
                            // can just continue as normal. We also expect that the return value is exactly 32 bytes
                            // long. If this isn't the case then we can safely ignore the result.
                            if (success && returndata.length == 32) {
                                // Although the expected value is a *boolean*, it's safer to decode as a uint256 in the
                                // case that the isUpgrading function returned something other than 0 or 1. But we only
                                // really care about the case where this value is 0 (= false).
                                uint256 ret = abi.decode(returndata, (uint256));
                                require(ret == 0, "L1ChugSplashProxy: system is currently being upgraded");
                            }
                            _;
                        }
                        /**
                         * @notice Makes a proxy call instead of triggering the given function when the caller is
                         *         either the owner or the zero address. Caller can only ever be the zero address if
                         *         this function is being called off-chain via eth_call, which is totally fine and can
                         *         be convenient for client-side tooling. Avoids situations where the proxy and
                         *         implementation share a sighash and the proxy function ends up being called instead
                         *         of the implementation one.
                         *
                         *         Note: msg.sender == address(0) can ONLY be triggered off-chain via eth_call. If
                         *         there's a way for someone to send a transaction with msg.sender == address(0) in any
                         *         real context then we have much bigger problems. Primary reason to include this
                         *         additional allowed sender is because the owner address can be changed dynamically
                         *         and we do not want clients to have to keep track of the current owner in order to
                         *         make an eth_call that doesn't trigger the proxied contract.
                         */
                        // slither-disable-next-line incorrect-modifier
                        modifier proxyCallIfNotOwner() {
                            if (msg.sender == _getOwner() || msg.sender == address(0)) {
                                _;
                            } else {
                                // This WILL halt the call frame on completion.
                                _doProxyCall();
                            }
                        }
                        /**
                         * @param _owner Address of the initial contract owner.
                         */
                        constructor(address _owner) {
                            _setOwner(_owner);
                        }
                        // slither-disable-next-line locked-ether
                        receive() external payable {
                            // Proxy call by default.
                            _doProxyCall();
                        }
                        // slither-disable-next-line locked-ether
                        fallback() external payable {
                            // Proxy call by default.
                            _doProxyCall();
                        }
                        /**
                         * @notice Sets the code that should be running behind this proxy.
                         *
                         *         Note: This scheme is a bit different from the standard proxy scheme where one would
                         *         typically deploy the code separately and then set the implementation address. We're
                         *         doing it this way because it gives us a lot more freedom on the client side. Can
                         *         only be triggered by the contract owner.
                         *
                         * @param _code New contract code to run inside this contract.
                         */
                        function setCode(bytes memory _code) external proxyCallIfNotOwner {
                            // Get the code hash of the current implementation.
                            address implementation = _getImplementation();
                            // If the code hash matches the new implementation then we return early.
                            if (keccak256(_code) == _getAccountCodeHash(implementation)) {
                                return;
                            }
                            // Create the deploycode by appending the magic prefix.
                            bytes memory deploycode = abi.encodePacked(DEPLOY_CODE_PREFIX, _code);
                            // Deploy the code and set the new implementation address.
                            address newImplementation;
                            assembly {
                                newImplementation := create(0x0, add(deploycode, 0x20), mload(deploycode))
                            }
                            // Check that the code was actually deployed correctly. I'm not sure if you can ever
                            // actually fail this check. Should only happen if the contract creation from above runs
                            // out of gas but this parent execution thread does NOT run out of gas. Seems like we
                            // should be doing this check anyway though.
                            require(
                                _getAccountCodeHash(newImplementation) == keccak256(_code),
                                "L1ChugSplashProxy: code was not correctly deployed"
                            );
                            _setImplementation(newImplementation);
                        }
                        /**
                         * @notice Modifies some storage slot within the proxy contract. Gives us a lot of power to
                         *         perform upgrades in a more transparent way. Only callable by the owner.
                         *
                         * @param _key   Storage key to modify.
                         * @param _value New value for the storage key.
                         */
                        function setStorage(bytes32 _key, bytes32 _value) external proxyCallIfNotOwner {
                            assembly {
                                sstore(_key, _value)
                            }
                        }
                        /**
                         * @notice Changes the owner of the proxy contract. Only callable by the owner.
                         *
                         * @param _owner New owner of the proxy contract.
                         */
                        function setOwner(address _owner) external proxyCallIfNotOwner {
                            _setOwner(_owner);
                        }
                        /**
                         * @notice Queries the owner of the proxy contract. Can only be called by the owner OR by
                         *         making an eth_call and setting the "from" address to address(0).
                         *
                         * @return Owner address.
                         */
                        function getOwner() external proxyCallIfNotOwner returns (address) {
                            return _getOwner();
                        }
                        /**
                         * @notice Queries the implementation address. Can only be called by the owner OR by making an
                         *         eth_call and setting the "from" address to address(0).
                         *
                         * @return Implementation address.
                         */
                        function getImplementation() external proxyCallIfNotOwner returns (address) {
                            return _getImplementation();
                        }
                        /**
                         * @notice Sets the implementation address.
                         *
                         * @param _implementation New implementation address.
                         */
                        function _setImplementation(address _implementation) internal {
                            assembly {
                                sstore(IMPLEMENTATION_KEY, _implementation)
                            }
                        }
                        /**
                         * @notice Changes the owner of the proxy contract.
                         *
                         * @param _owner New owner of the proxy contract.
                         */
                        function _setOwner(address _owner) internal {
                            assembly {
                                sstore(OWNER_KEY, _owner)
                            }
                        }
                        /**
                         * @notice Performs the proxy call via a delegatecall.
                         */
                        function _doProxyCall() internal onlyWhenNotPaused {
                            address implementation = _getImplementation();
                            require(implementation != address(0), "L1ChugSplashProxy: implementation is not set yet");
                            assembly {
                                // Copy calldata into memory at 0x0....calldatasize.
                                calldatacopy(0x0, 0x0, calldatasize())
                                // Perform the delegatecall, make sure to pass all available gas.
                                let success := delegatecall(gas(), implementation, 0x0, calldatasize(), 0x0, 0x0)
                                // Copy returndata into memory at 0x0....returndatasize. Note that this *will*
                                // overwrite the calldata that we just copied into memory but that doesn't really
                                // matter because we'll be returning in a second anyway.
                                returndatacopy(0x0, 0x0, returndatasize())
                                // Success == 0 means a revert. We'll revert too and pass the data up.
                                if iszero(success) {
                                    revert(0x0, returndatasize())
                                }
                                // Otherwise we'll just return and pass the data up.
                                return(0x0, returndatasize())
                            }
                        }
                        /**
                         * @notice Queries the implementation address.
                         *
                         * @return Implementation address.
                         */
                        function _getImplementation() internal view returns (address) {
                            address implementation;
                            assembly {
                                implementation := sload(IMPLEMENTATION_KEY)
                            }
                            return implementation;
                        }
                        /**
                         * @notice Queries the owner of the proxy contract.
                         *
                         * @return Owner address.
                         */
                        function _getOwner() internal view returns (address) {
                            address owner;
                            assembly {
                                owner := sload(OWNER_KEY)
                            }
                            return owner;
                        }
                        /**
                         * @notice Gets the code hash for a given account.
                         *
                         * @param _account Address of the account to get a code hash for.
                         *
                         * @return Code hash for the account.
                         */
                        function _getAccountCodeHash(address _account) internal view returns (bytes32) {
                            bytes32 codeHash;
                            assembly {
                                codeHash := extcodehash(_account)
                            }
                            return codeHash;
                        }
                    }
                    

                    File 2 of 11: FiatTokenProxy
                    pragma solidity ^0.4.24;
                    
                    // File: zos-lib/contracts/upgradeability/Proxy.sol
                    
                    /**
                     * @title Proxy
                     * @dev Implements delegation of calls to other contracts, with proper
                     * forwarding of return values and bubbling of failures.
                     * It defines a fallback function that delegates all calls to the address
                     * returned by the abstract _implementation() internal function.
                     */
                    contract Proxy {
                      /**
                       * @dev Fallback function.
                       * Implemented entirely in `_fallback`.
                       */
                      function () payable external {
                        _fallback();
                      }
                    
                      /**
                       * @return The Address of the implementation.
                       */
                      function _implementation() internal view returns (address);
                    
                      /**
                       * @dev Delegates execution to an implementation contract.
                       * This is a low level function that doesn't return to its internal call site.
                       * It will return to the external caller whatever the implementation returns.
                       * @param implementation Address to delegate.
                       */
                      function _delegate(address implementation) internal {
                        assembly {
                          // Copy msg.data. We take full control of memory in this inline assembly
                          // block because it will not return to Solidity code. We overwrite the
                          // Solidity scratch pad at memory position 0.
                          calldatacopy(0, 0, calldatasize)
                    
                          // Call the implementation.
                          // out and outsize are 0 because we don't know the size yet.
                          let result := delegatecall(gas, implementation, 0, calldatasize, 0, 0)
                    
                          // Copy the returned data.
                          returndatacopy(0, 0, returndatasize)
                    
                          switch result
                          // delegatecall returns 0 on error.
                          case 0 { revert(0, returndatasize) }
                          default { return(0, returndatasize) }
                        }
                      }
                    
                      /**
                       * @dev Function that is run as the first thing in the fallback function.
                       * Can be redefined in derived contracts to add functionality.
                       * Redefinitions must call super._willFallback().
                       */
                      function _willFallback() internal {
                      }
                    
                      /**
                       * @dev fallback implementation.
                       * Extracted to enable manual triggering.
                       */
                      function _fallback() internal {
                        _willFallback();
                        _delegate(_implementation());
                      }
                    }
                    
                    // File: openzeppelin-solidity/contracts/AddressUtils.sol
                    
                    /**
                     * Utility library of inline functions on addresses
                     */
                    library AddressUtils {
                    
                      /**
                       * Returns whether the target address is a contract
                       * @dev This function will return false if invoked during the constructor of a contract,
                       * as the code is not actually created until after the constructor finishes.
                       * @param addr address to check
                       * @return whether the target address is a contract
                       */
                      function isContract(address addr) internal view returns (bool) {
                        uint256 size;
                        // XXX Currently there is no better way to check if there is a contract in an address
                        // than to check the size of the code at that address.
                        // See https://ethereum.stackexchange.com/a/14016/36603
                        // for more details about how this works.
                        // TODO Check this again before the Serenity release, because all addresses will be
                        // contracts then.
                        // solium-disable-next-line security/no-inline-assembly
                        assembly { size := extcodesize(addr) }
                        return size > 0;
                      }
                    
                    }
                    
                    // File: zos-lib/contracts/upgradeability/UpgradeabilityProxy.sol
                    
                    /**
                     * @title UpgradeabilityProxy
                     * @dev This contract implements a proxy that allows to change the
                     * implementation address to which it will delegate.
                     * Such a change is called an implementation upgrade.
                     */
                    contract UpgradeabilityProxy is Proxy {
                      /**
                       * @dev Emitted when the implementation is upgraded.
                       * @param implementation Address of the new implementation.
                       */
                      event Upgraded(address implementation);
                    
                      /**
                       * @dev Storage slot with the address of the current implementation.
                       * This is the keccak-256 hash of "org.zeppelinos.proxy.implementation", and is
                       * validated in the constructor.
                       */
                      bytes32 private constant IMPLEMENTATION_SLOT = 0x7050c9e0f4ca769c69bd3a8ef740bc37934f8e2c036e5a723fd8ee048ed3f8c3;
                    
                      /**
                       * @dev Contract constructor.
                       * @param _implementation Address of the initial implementation.
                       */
                      constructor(address _implementation) public {
                        assert(IMPLEMENTATION_SLOT == keccak256("org.zeppelinos.proxy.implementation"));
                    
                        _setImplementation(_implementation);
                      }
                    
                      /**
                       * @dev Returns the current implementation.
                       * @return Address of the current implementation
                       */
                      function _implementation() internal view returns (address impl) {
                        bytes32 slot = IMPLEMENTATION_SLOT;
                        assembly {
                          impl := sload(slot)
                        }
                      }
                    
                      /**
                       * @dev Upgrades the proxy to a new implementation.
                       * @param newImplementation Address of the new implementation.
                       */
                      function _upgradeTo(address newImplementation) internal {
                        _setImplementation(newImplementation);
                        emit Upgraded(newImplementation);
                      }
                    
                      /**
                       * @dev Sets the implementation address of the proxy.
                       * @param newImplementation Address of the new implementation.
                       */
                      function _setImplementation(address newImplementation) private {
                        require(AddressUtils.isContract(newImplementation), "Cannot set a proxy implementation to a non-contract address");
                    
                        bytes32 slot = IMPLEMENTATION_SLOT;
                    
                        assembly {
                          sstore(slot, newImplementation)
                        }
                      }
                    }
                    
                    // File: zos-lib/contracts/upgradeability/AdminUpgradeabilityProxy.sol
                    
                    /**
                     * @title AdminUpgradeabilityProxy
                     * @dev This contract combines an upgradeability proxy with an authorization
                     * mechanism for administrative tasks.
                     * All external functions in this contract must be guarded by the
                     * `ifAdmin` modifier. See ethereum/solidity#3864 for a Solidity
                     * feature proposal that would enable this to be done automatically.
                     */
                    contract AdminUpgradeabilityProxy is UpgradeabilityProxy {
                      /**
                       * @dev Emitted when the administration has been transferred.
                       * @param previousAdmin Address of the previous admin.
                       * @param newAdmin Address of the new admin.
                       */
                      event AdminChanged(address previousAdmin, address newAdmin);
                    
                      /**
                       * @dev Storage slot with the admin of the contract.
                       * This is the keccak-256 hash of "org.zeppelinos.proxy.admin", and is
                       * validated in the constructor.
                       */
                      bytes32 private constant ADMIN_SLOT = 0x10d6a54a4754c8869d6886b5f5d7fbfa5b4522237ea5c60d11bc4e7a1ff9390b;
                    
                      /**
                       * @dev Modifier to check whether the `msg.sender` is the admin.
                       * If it is, it will run the function. Otherwise, it will delegate the call
                       * to the implementation.
                       */
                      modifier ifAdmin() {
                        if (msg.sender == _admin()) {
                          _;
                        } else {
                          _fallback();
                        }
                      }
                    
                      /**
                       * Contract constructor.
                       * It sets the `msg.sender` as the proxy administrator.
                       * @param _implementation address of the initial implementation.
                       */
                      constructor(address _implementation) UpgradeabilityProxy(_implementation) public {
                        assert(ADMIN_SLOT == keccak256("org.zeppelinos.proxy.admin"));
                    
                        _setAdmin(msg.sender);
                      }
                    
                      /**
                       * @return The address of the proxy admin.
                       */
                      function admin() external view ifAdmin returns (address) {
                        return _admin();
                      }
                    
                      /**
                       * @return The address of the implementation.
                       */
                      function implementation() external view ifAdmin returns (address) {
                        return _implementation();
                      }
                    
                      /**
                       * @dev Changes the admin of the proxy.
                       * Only the current admin can call this function.
                       * @param newAdmin Address to transfer proxy administration to.
                       */
                      function changeAdmin(address newAdmin) external ifAdmin {
                        require(newAdmin != address(0), "Cannot change the admin of a proxy to the zero address");
                        emit AdminChanged(_admin(), newAdmin);
                        _setAdmin(newAdmin);
                      }
                    
                      /**
                       * @dev Upgrade the backing implementation of the proxy.
                       * Only the admin can call this function.
                       * @param newImplementation Address of the new implementation.
                       */
                      function upgradeTo(address newImplementation) external ifAdmin {
                        _upgradeTo(newImplementation);
                      }
                    
                      /**
                       * @dev Upgrade the backing implementation of the proxy and call a function
                       * on the new implementation.
                       * This is useful to initialize the proxied contract.
                       * @param newImplementation Address of the new implementation.
                       * @param data Data to send as msg.data in the low level call.
                       * It should include the signature and the parameters of the function to be
                       * called, as described in
                       * https://solidity.readthedocs.io/en/develop/abi-spec.html#function-selector-and-argument-encoding.
                       */
                      function upgradeToAndCall(address newImplementation, bytes data) payable external ifAdmin {
                        _upgradeTo(newImplementation);
                        require(address(this).call.value(msg.value)(data));
                      }
                    
                      /**
                       * @return The admin slot.
                       */
                      function _admin() internal view returns (address adm) {
                        bytes32 slot = ADMIN_SLOT;
                        assembly {
                          adm := sload(slot)
                        }
                      }
                    
                      /**
                       * @dev Sets the address of the proxy admin.
                       * @param newAdmin Address of the new proxy admin.
                       */
                      function _setAdmin(address newAdmin) internal {
                        bytes32 slot = ADMIN_SLOT;
                    
                        assembly {
                          sstore(slot, newAdmin)
                        }
                      }
                    
                      /**
                       * @dev Only fall back when the sender is not the admin.
                       */
                      function _willFallback() internal {
                        require(msg.sender != _admin(), "Cannot call fallback function from the proxy admin");
                        super._willFallback();
                      }
                    }
                    
                    // File: contracts/FiatTokenProxy.sol
                    
                    /**
                    * Copyright CENTRE SECZ 2018
                    *
                    * Permission is hereby granted, free of charge, to any person obtaining a copy 
                    * of this software and associated documentation files (the "Software"), to deal 
                    * in the Software without restriction, including without limitation the rights 
                    * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 
                    * copies of the Software, and to permit persons to whom the Software is furnished to 
                    * do so, subject to the following conditions:
                    *
                    * The above copyright notice and this permission notice shall be included in all 
                    * copies or substantial portions of the Software.
                    *
                    * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 
                    * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 
                    * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 
                    * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
                    * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN 
                    * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
                    */
                    
                    pragma solidity ^0.4.24;
                    
                    
                    /**
                     * @title FiatTokenProxy
                     * @dev This contract proxies FiatToken calls and enables FiatToken upgrades
                    */ 
                    contract FiatTokenProxy is AdminUpgradeabilityProxy {
                        constructor(address _implementation) public AdminUpgradeabilityProxy(_implementation) {
                        }
                    }

                    File 3 of 11: Proxy
                    // SPDX-License-Identifier: MIT
                    pragma solidity 0.8.15;
                    /**
                     * @title Proxy
                     * @notice Proxy is a transparent proxy that passes through the call if the caller is the owner or
                     *         if the caller is address(0), meaning that the call originated from an off-chain
                     *         simulation.
                     */
                    contract Proxy {
                        /**
                         * @notice The storage slot that holds the address of the implementation.
                         *         bytes32(uint256(keccak256('eip1967.proxy.implementation')) - 1)
                         */
                        bytes32 internal constant IMPLEMENTATION_KEY =
                            0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;
                        /**
                         * @notice The storage slot that holds the address of the owner.
                         *         bytes32(uint256(keccak256('eip1967.proxy.admin')) - 1)
                         */
                        bytes32 internal constant OWNER_KEY =
                            0xb53127684a568b3173ae13b9f8a6016e243e63b6e8ee1178d6a717850b5d6103;
                        /**
                         * @notice An event that is emitted each time the implementation is changed. This event is part
                         *         of the EIP-1967 specification.
                         *
                         * @param implementation The address of the implementation contract
                         */
                        event Upgraded(address indexed implementation);
                        /**
                         * @notice An event that is emitted each time the owner is upgraded. This event is part of the
                         *         EIP-1967 specification.
                         *
                         * @param previousAdmin The previous owner of the contract
                         * @param newAdmin      The new owner of the contract
                         */
                        event AdminChanged(address previousAdmin, address newAdmin);
                        /**
                         * @notice A modifier that reverts if not called by the owner or by address(0) to allow
                         *         eth_call to interact with this proxy without needing to use low-level storage
                         *         inspection. We assume that nobody is able to trigger calls from address(0) during
                         *         normal EVM execution.
                         */
                        modifier proxyCallIfNotAdmin() {
                            if (msg.sender == _getAdmin() || msg.sender == address(0)) {
                                _;
                            } else {
                                // This WILL halt the call frame on completion.
                                _doProxyCall();
                            }
                        }
                        /**
                         * @notice Sets the initial admin during contract deployment. Admin address is stored at the
                         *         EIP-1967 admin storage slot so that accidental storage collision with the
                         *         implementation is not possible.
                         *
                         * @param _admin Address of the initial contract admin. Admin as the ability to access the
                         *               transparent proxy interface.
                         */
                        constructor(address _admin) {
                            _changeAdmin(_admin);
                        }
                        // slither-disable-next-line locked-ether
                        receive() external payable {
                            // Proxy call by default.
                            _doProxyCall();
                        }
                        // slither-disable-next-line locked-ether
                        fallback() external payable {
                            // Proxy call by default.
                            _doProxyCall();
                        }
                        /**
                         * @notice Set the implementation contract address. The code at the given address will execute
                         *         when this contract is called.
                         *
                         * @param _implementation Address of the implementation contract.
                         */
                        function upgradeTo(address _implementation) public virtual proxyCallIfNotAdmin {
                            _setImplementation(_implementation);
                        }
                        /**
                         * @notice Set the implementation and call a function in a single transaction. Useful to ensure
                         *         atomic execution of initialization-based upgrades.
                         *
                         * @param _implementation Address of the implementation contract.
                         * @param _data           Calldata to delegatecall the new implementation with.
                         */
                        function upgradeToAndCall(address _implementation, bytes calldata _data)
                            public
                            payable
                            virtual
                            proxyCallIfNotAdmin
                            returns (bytes memory)
                        {
                            _setImplementation(_implementation);
                            (bool success, bytes memory returndata) = _implementation.delegatecall(_data);
                            require(success, "Proxy: delegatecall to new implementation contract failed");
                            return returndata;
                        }
                        /**
                         * @notice Changes the owner of the proxy contract. Only callable by the owner.
                         *
                         * @param _admin New owner of the proxy contract.
                         */
                        function changeAdmin(address _admin) public virtual proxyCallIfNotAdmin {
                            _changeAdmin(_admin);
                        }
                        /**
                         * @notice Gets the owner of the proxy contract.
                         *
                         * @return Owner address.
                         */
                        function admin() public virtual proxyCallIfNotAdmin returns (address) {
                            return _getAdmin();
                        }
                        /**
                         * @notice Queries the implementation address.
                         *
                         * @return Implementation address.
                         */
                        function implementation() public virtual proxyCallIfNotAdmin returns (address) {
                            return _getImplementation();
                        }
                        /**
                         * @notice Sets the implementation address.
                         *
                         * @param _implementation New implementation address.
                         */
                        function _setImplementation(address _implementation) internal {
                            assembly {
                                sstore(IMPLEMENTATION_KEY, _implementation)
                            }
                            emit Upgraded(_implementation);
                        }
                        /**
                         * @notice Changes the owner of the proxy contract.
                         *
                         * @param _admin New owner of the proxy contract.
                         */
                        function _changeAdmin(address _admin) internal {
                            address previous = _getAdmin();
                            assembly {
                                sstore(OWNER_KEY, _admin)
                            }
                            emit AdminChanged(previous, _admin);
                        }
                        /**
                         * @notice Performs the proxy call via a delegatecall.
                         */
                        function _doProxyCall() internal {
                            address impl = _getImplementation();
                            require(impl != address(0), "Proxy: implementation not initialized");
                            assembly {
                                // Copy calldata into memory at 0x0....calldatasize.
                                calldatacopy(0x0, 0x0, calldatasize())
                                // Perform the delegatecall, make sure to pass all available gas.
                                let success := delegatecall(gas(), impl, 0x0, calldatasize(), 0x0, 0x0)
                                // Copy returndata into memory at 0x0....returndatasize. Note that this *will*
                                // overwrite the calldata that we just copied into memory but that doesn't really
                                // matter because we'll be returning in a second anyway.
                                returndatacopy(0x0, 0x0, returndatasize())
                                // Success == 0 means a revert. We'll revert too and pass the data up.
                                if iszero(success) {
                                    revert(0x0, returndatasize())
                                }
                                // Otherwise we'll just return and pass the data up.
                                return(0x0, returndatasize())
                            }
                        }
                        /**
                         * @notice Queries the implementation address.
                         *
                         * @return Implementation address.
                         */
                        function _getImplementation() internal view returns (address) {
                            address impl;
                            assembly {
                                impl := sload(IMPLEMENTATION_KEY)
                            }
                            return impl;
                        }
                        /**
                         * @notice Queries the owner of the proxy contract.
                         *
                         * @return Owner address.
                         */
                        function _getAdmin() internal view returns (address) {
                            address owner;
                            assembly {
                                owner := sload(OWNER_KEY)
                            }
                            return owner;
                        }
                    }
                    

                    File 4 of 11: ResolvedDelegateProxy
                    // SPDX-License-Identifier: MIT
                    pragma solidity 0.8.15;
                    import { AddressManager } from "./AddressManager.sol";
                    /**
                     * @custom:legacy
                     * @title ResolvedDelegateProxy
                     * @notice ResolvedDelegateProxy is a legacy proxy contract that makes use of the AddressManager to
                     *         resolve the implementation address. We're maintaining this contract for backwards
                     *         compatibility so we can manage all legacy proxies where necessary.
                     */
                    contract ResolvedDelegateProxy {
                        /**
                         * @notice Mapping used to store the implementation name that corresponds to this contract. A
                         *         mapping was originally used as a way to bypass the same issue normally solved by
                         *         storing the implementation address in a specific storage slot that does not conflict
                         *         with any other storage slot. Generally NOT a safe solution but works as long as the
                         *         implementation does not also keep a mapping in the first storage slot.
                         */
                        mapping(address => string) private implementationName;
                        /**
                         * @notice Mapping used to store the address of the AddressManager contract where the
                         *         implementation address will be resolved from. Same concept here as with the above
                         *         mapping. Also generally unsafe but fine if the implementation doesn't keep a mapping
                         *         in the second storage slot.
                         */
                        mapping(address => AddressManager) private addressManager;
                        /**
                         * @param _addressManager  Address of the AddressManager.
                         * @param _implementationName implementationName of the contract to proxy to.
                         */
                        constructor(AddressManager _addressManager, string memory _implementationName) {
                            addressManager[address(this)] = _addressManager;
                            implementationName[address(this)] = _implementationName;
                        }
                        /**
                         * @notice Fallback, performs a delegatecall to the resolved implementation address.
                         */
                        // solhint-disable-next-line no-complex-fallback
                        fallback() external payable {
                            address target = addressManager[address(this)].getAddress(
                                (implementationName[address(this)])
                            );
                            require(target != address(0), "ResolvedDelegateProxy: target address must be initialized");
                            // slither-disable-next-line controlled-delegatecall
                            (bool success, bytes memory returndata) = target.delegatecall(msg.data);
                            if (success == true) {
                                assembly {
                                    return(add(returndata, 0x20), mload(returndata))
                                }
                            } else {
                                assembly {
                                    revert(add(returndata, 0x20), mload(returndata))
                                }
                            }
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    pragma solidity 0.8.15;
                    import { Ownable } from "@openzeppelin/contracts/access/Ownable.sol";
                    /**
                     * @custom:legacy
                     * @title AddressManager
                     * @notice AddressManager is a legacy contract that was used in the old version of the Optimism
                     *         system to manage a registry of string names to addresses. We now use a more standard
                     *         proxy system instead, but this contract is still necessary for backwards compatibility
                     *         with several older contracts.
                     */
                    contract AddressManager is Ownable {
                        /**
                         * @notice Mapping of the hashes of string names to addresses.
                         */
                        mapping(bytes32 => address) private addresses;
                        /**
                         * @notice Emitted when an address is modified in the registry.
                         *
                         * @param name       String name being set in the registry.
                         * @param newAddress Address set for the given name.
                         * @param oldAddress Address that was previously set for the given name.
                         */
                        event AddressSet(string indexed name, address newAddress, address oldAddress);
                        /**
                         * @notice Changes the address associated with a particular name.
                         *
                         * @param _name    String name to associate an address with.
                         * @param _address Address to associate with the name.
                         */
                        function setAddress(string memory _name, address _address) external onlyOwner {
                            bytes32 nameHash = _getNameHash(_name);
                            address oldAddress = addresses[nameHash];
                            addresses[nameHash] = _address;
                            emit AddressSet(_name, _address, oldAddress);
                        }
                        /**
                         * @notice Retrieves the address associated with a given name.
                         *
                         * @param _name Name to retrieve an address for.
                         *
                         * @return Address associated with the given name.
                         */
                        function getAddress(string memory _name) external view returns (address) {
                            return addresses[_getNameHash(_name)];
                        }
                        /**
                         * @notice Computes the hash of a name.
                         *
                         * @param _name Name to compute a hash for.
                         *
                         * @return Hash of the given name.
                         */
                        function _getNameHash(string memory _name) internal pure returns (bytes32) {
                            return keccak256(abi.encodePacked(_name));
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    // OpenZeppelin Contracts (last updated v4.7.0) (access/Ownable.sol)
                    pragma solidity ^0.8.0;
                    abstract contract Context {
                        function _msgSender() internal view virtual returns (address) {
                            return msg.sender;
                        }
                        function _msgData() internal view virtual returns (bytes calldata) {
                            return msg.data;
                        }
                    }
                    /**
                     * @dev Contract module which provides a basic access control mechanism, where
                     * there is an account (an owner) that can be granted exclusive access to
                     * specific functions.
                     *
                     * By default, the owner account will be the one that deploys the contract. This
                     * can later be changed with {transferOwnership}.
                     *
                     * This module is used through inheritance. It will make available the modifier
                     * `onlyOwner`, which can be applied to your functions to restrict their use to
                     * the owner.
                     */
                    abstract contract Ownable is Context {
                        address private _owner;
                        event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
                        /**
                         * @dev Initializes the contract setting the deployer as the initial owner.
                         */
                        constructor() {
                            _transferOwnership(_msgSender());
                        }
                        /**
                         * @dev Throws if called by any account other than the owner.
                         */
                        modifier onlyOwner() {
                            _checkOwner();
                            _;
                        }
                        /**
                         * @dev Returns the address of the current owner.
                         */
                        function owner() public view virtual returns (address) {
                            return _owner;
                        }
                        /**
                         * @dev Throws if the sender is not the owner.
                         */
                        function _checkOwner() internal view virtual {
                            require(owner() == _msgSender(), "Ownable: caller is not the owner");
                        }
                        /**
                         * @dev Leaves the contract without owner. It will not be possible to call
                         * `onlyOwner` functions anymore. Can only be called by the current owner.
                         *
                         * NOTE: Renouncing ownership will leave the contract without an owner,
                         * thereby removing any functionality that is only available to the owner.
                         */
                        function renounceOwnership() public virtual onlyOwner {
                            _transferOwnership(address(0));
                        }
                        /**
                         * @dev Transfers ownership of the contract to a new account (`newOwner`).
                         * Can only be called by the current owner.
                         */
                        function transferOwnership(address newOwner) public virtual onlyOwner {
                            require(newOwner != address(0), "Ownable: new owner is the zero address");
                            _transferOwnership(newOwner);
                        }
                        /**
                         * @dev Transfers ownership of the contract to a new account (`newOwner`).
                         * Internal function without access restriction.
                         */
                        function _transferOwnership(address newOwner) internal virtual {
                            address oldOwner = _owner;
                            _owner = newOwner;
                            emit OwnershipTransferred(oldOwner, newOwner);
                        }
                    }
                    

                    File 5 of 11: ProxyAdmin
                    // SPDX-License-Identifier: MIT
                    pragma solidity 0.8.15;
                    import { Ownable } from "@openzeppelin/contracts/access/Ownable.sol";
                    /**
                     * @custom:legacy
                     * @title AddressManager
                     * @notice AddressManager is a legacy contract that was used in the old version of the Optimism
                     *         system to manage a registry of string names to addresses. We now use a more standard
                     *         proxy system instead, but this contract is still necessary for backwards compatibility
                     *         with several older contracts.
                     */
                    contract AddressManager is Ownable {
                        /**
                         * @notice Mapping of the hashes of string names to addresses.
                         */
                        mapping(bytes32 => address) private addresses;
                        /**
                         * @notice Emitted when an address is modified in the registry.
                         *
                         * @param name       String name being set in the registry.
                         * @param newAddress Address set for the given name.
                         * @param oldAddress Address that was previously set for the given name.
                         */
                        event AddressSet(string indexed name, address newAddress, address oldAddress);
                        /**
                         * @notice Changes the address associated with a particular name.
                         *
                         * @param _name    String name to associate an address with.
                         * @param _address Address to associate with the name.
                         */
                        function setAddress(string memory _name, address _address) external onlyOwner {
                            bytes32 nameHash = _getNameHash(_name);
                            address oldAddress = addresses[nameHash];
                            addresses[nameHash] = _address;
                            emit AddressSet(_name, _address, oldAddress);
                        }
                        /**
                         * @notice Retrieves the address associated with a given name.
                         *
                         * @param _name Name to retrieve an address for.
                         *
                         * @return Address associated with the given name.
                         */
                        function getAddress(string memory _name) external view returns (address) {
                            return addresses[_getNameHash(_name)];
                        }
                        /**
                         * @notice Computes the hash of a name.
                         *
                         * @param _name Name to compute a hash for.
                         *
                         * @return Hash of the given name.
                         */
                        function _getNameHash(string memory _name) internal pure returns (bytes32) {
                            return keccak256(abi.encodePacked(_name));
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    pragma solidity 0.8.15;
                    /**
                     * @title IL1ChugSplashDeployer
                     */
                    interface IL1ChugSplashDeployer {
                        function isUpgrading() external view returns (bool);
                    }
                    /**
                     * @custom:legacy
                     * @title L1ChugSplashProxy
                     * @notice Basic ChugSplash proxy contract for L1. Very close to being a normal proxy but has added
                     *         functions `setCode` and `setStorage` for changing the code or storage of the contract.
                     *
                     *         Note for future developers: do NOT make anything in this contract 'public' unless you
                     *         know what you're doing. Anything public can potentially have a function signature that
                     *         conflicts with a signature attached to the implementation contract. Public functions
                     *         SHOULD always have the `proxyCallIfNotOwner` modifier unless there's some *really* good
                     *         reason not to have that modifier. And there almost certainly is not a good reason to not
                     *         have that modifier. Beware!
                     */
                    contract L1ChugSplashProxy {
                        /**
                         * @notice "Magic" prefix. When prepended to some arbitrary bytecode and used to create a
                         *         contract, the appended bytecode will be deployed as given.
                         */
                        bytes13 internal constant DEPLOY_CODE_PREFIX = 0x600D380380600D6000396000f3;
                        /**
                         * @notice bytes32(uint256(keccak256('eip1967.proxy.implementation')) - 1)
                         */
                        bytes32 internal constant IMPLEMENTATION_KEY =
                            0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;
                        /**
                         * @notice bytes32(uint256(keccak256('eip1967.proxy.admin')) - 1)
                         */
                        bytes32 internal constant OWNER_KEY =
                            0xb53127684a568b3173ae13b9f8a6016e243e63b6e8ee1178d6a717850b5d6103;
                        /**
                         * @notice Blocks a function from being called when the parent signals that the system should
                         *         be paused via an isUpgrading function.
                         */
                        modifier onlyWhenNotPaused() {
                            address owner = _getOwner();
                            // We do a low-level call because there's no guarantee that the owner actually *is* an
                            // L1ChugSplashDeployer contract and Solidity will throw errors if we do a normal call and
                            // it turns out that it isn't the right type of contract.
                            (bool success, bytes memory returndata) = owner.staticcall(
                                abi.encodeWithSelector(IL1ChugSplashDeployer.isUpgrading.selector)
                            );
                            // If the call was unsuccessful then we assume that there's no "isUpgrading" method and we
                            // can just continue as normal. We also expect that the return value is exactly 32 bytes
                            // long. If this isn't the case then we can safely ignore the result.
                            if (success && returndata.length == 32) {
                                // Although the expected value is a *boolean*, it's safer to decode as a uint256 in the
                                // case that the isUpgrading function returned something other than 0 or 1. But we only
                                // really care about the case where this value is 0 (= false).
                                uint256 ret = abi.decode(returndata, (uint256));
                                require(ret == 0, "L1ChugSplashProxy: system is currently being upgraded");
                            }
                            _;
                        }
                        /**
                         * @notice Makes a proxy call instead of triggering the given function when the caller is
                         *         either the owner or the zero address. Caller can only ever be the zero address if
                         *         this function is being called off-chain via eth_call, which is totally fine and can
                         *         be convenient for client-side tooling. Avoids situations where the proxy and
                         *         implementation share a sighash and the proxy function ends up being called instead
                         *         of the implementation one.
                         *
                         *         Note: msg.sender == address(0) can ONLY be triggered off-chain via eth_call. If
                         *         there's a way for someone to send a transaction with msg.sender == address(0) in any
                         *         real context then we have much bigger problems. Primary reason to include this
                         *         additional allowed sender is because the owner address can be changed dynamically
                         *         and we do not want clients to have to keep track of the current owner in order to
                         *         make an eth_call that doesn't trigger the proxied contract.
                         */
                        // slither-disable-next-line incorrect-modifier
                        modifier proxyCallIfNotOwner() {
                            if (msg.sender == _getOwner() || msg.sender == address(0)) {
                                _;
                            } else {
                                // This WILL halt the call frame on completion.
                                _doProxyCall();
                            }
                        }
                        /**
                         * @param _owner Address of the initial contract owner.
                         */
                        constructor(address _owner) {
                            _setOwner(_owner);
                        }
                        // slither-disable-next-line locked-ether
                        receive() external payable {
                            // Proxy call by default.
                            _doProxyCall();
                        }
                        // slither-disable-next-line locked-ether
                        fallback() external payable {
                            // Proxy call by default.
                            _doProxyCall();
                        }
                        /**
                         * @notice Sets the code that should be running behind this proxy.
                         *
                         *         Note: This scheme is a bit different from the standard proxy scheme where one would
                         *         typically deploy the code separately and then set the implementation address. We're
                         *         doing it this way because it gives us a lot more freedom on the client side. Can
                         *         only be triggered by the contract owner.
                         *
                         * @param _code New contract code to run inside this contract.
                         */
                        function setCode(bytes memory _code) external proxyCallIfNotOwner {
                            // Get the code hash of the current implementation.
                            address implementation = _getImplementation();
                            // If the code hash matches the new implementation then we return early.
                            if (keccak256(_code) == _getAccountCodeHash(implementation)) {
                                return;
                            }
                            // Create the deploycode by appending the magic prefix.
                            bytes memory deploycode = abi.encodePacked(DEPLOY_CODE_PREFIX, _code);
                            // Deploy the code and set the new implementation address.
                            address newImplementation;
                            assembly {
                                newImplementation := create(0x0, add(deploycode, 0x20), mload(deploycode))
                            }
                            // Check that the code was actually deployed correctly. I'm not sure if you can ever
                            // actually fail this check. Should only happen if the contract creation from above runs
                            // out of gas but this parent execution thread does NOT run out of gas. Seems like we
                            // should be doing this check anyway though.
                            require(
                                _getAccountCodeHash(newImplementation) == keccak256(_code),
                                "L1ChugSplashProxy: code was not correctly deployed"
                            );
                            _setImplementation(newImplementation);
                        }
                        /**
                         * @notice Modifies some storage slot within the proxy contract. Gives us a lot of power to
                         *         perform upgrades in a more transparent way. Only callable by the owner.
                         *
                         * @param _key   Storage key to modify.
                         * @param _value New value for the storage key.
                         */
                        function setStorage(bytes32 _key, bytes32 _value) external proxyCallIfNotOwner {
                            assembly {
                                sstore(_key, _value)
                            }
                        }
                        /**
                         * @notice Changes the owner of the proxy contract. Only callable by the owner.
                         *
                         * @param _owner New owner of the proxy contract.
                         */
                        function setOwner(address _owner) external proxyCallIfNotOwner {
                            _setOwner(_owner);
                        }
                        /**
                         * @notice Queries the owner of the proxy contract. Can only be called by the owner OR by
                         *         making an eth_call and setting the "from" address to address(0).
                         *
                         * @return Owner address.
                         */
                        function getOwner() external proxyCallIfNotOwner returns (address) {
                            return _getOwner();
                        }
                        /**
                         * @notice Queries the implementation address. Can only be called by the owner OR by making an
                         *         eth_call and setting the "from" address to address(0).
                         *
                         * @return Implementation address.
                         */
                        function getImplementation() external proxyCallIfNotOwner returns (address) {
                            return _getImplementation();
                        }
                        /**
                         * @notice Sets the implementation address.
                         *
                         * @param _implementation New implementation address.
                         */
                        function _setImplementation(address _implementation) internal {
                            assembly {
                                sstore(IMPLEMENTATION_KEY, _implementation)
                            }
                        }
                        /**
                         * @notice Changes the owner of the proxy contract.
                         *
                         * @param _owner New owner of the proxy contract.
                         */
                        function _setOwner(address _owner) internal {
                            assembly {
                                sstore(OWNER_KEY, _owner)
                            }
                        }
                        /**
                         * @notice Performs the proxy call via a delegatecall.
                         */
                        function _doProxyCall() internal onlyWhenNotPaused {
                            address implementation = _getImplementation();
                            require(implementation != address(0), "L1ChugSplashProxy: implementation is not set yet");
                            assembly {
                                // Copy calldata into memory at 0x0....calldatasize.
                                calldatacopy(0x0, 0x0, calldatasize())
                                // Perform the delegatecall, make sure to pass all available gas.
                                let success := delegatecall(gas(), implementation, 0x0, calldatasize(), 0x0, 0x0)
                                // Copy returndata into memory at 0x0....returndatasize. Note that this *will*
                                // overwrite the calldata that we just copied into memory but that doesn't really
                                // matter because we'll be returning in a second anyway.
                                returndatacopy(0x0, 0x0, returndatasize())
                                // Success == 0 means a revert. We'll revert too and pass the data up.
                                if iszero(success) {
                                    revert(0x0, returndatasize())
                                }
                                // Otherwise we'll just return and pass the data up.
                                return(0x0, returndatasize())
                            }
                        }
                        /**
                         * @notice Queries the implementation address.
                         *
                         * @return Implementation address.
                         */
                        function _getImplementation() internal view returns (address) {
                            address implementation;
                            assembly {
                                implementation := sload(IMPLEMENTATION_KEY)
                            }
                            return implementation;
                        }
                        /**
                         * @notice Queries the owner of the proxy contract.
                         *
                         * @return Owner address.
                         */
                        function _getOwner() internal view returns (address) {
                            address owner;
                            assembly {
                                owner := sload(OWNER_KEY)
                            }
                            return owner;
                        }
                        /**
                         * @notice Gets the code hash for a given account.
                         *
                         * @param _account Address of the account to get a code hash for.
                         *
                         * @return Code hash for the account.
                         */
                        function _getAccountCodeHash(address _account) internal view returns (bytes32) {
                            bytes32 codeHash;
                            assembly {
                                codeHash := extcodehash(_account)
                            }
                            return codeHash;
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    pragma solidity 0.8.15;
                    /**
                     * @title Proxy
                     * @notice Proxy is a transparent proxy that passes through the call if the caller is the owner or
                     *         if the caller is address(0), meaning that the call originated from an off-chain
                     *         simulation.
                     */
                    contract Proxy {
                        /**
                         * @notice The storage slot that holds the address of the implementation.
                         *         bytes32(uint256(keccak256('eip1967.proxy.implementation')) - 1)
                         */
                        bytes32 internal constant IMPLEMENTATION_KEY =
                            0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;
                        /**
                         * @notice The storage slot that holds the address of the owner.
                         *         bytes32(uint256(keccak256('eip1967.proxy.admin')) - 1)
                         */
                        bytes32 internal constant OWNER_KEY =
                            0xb53127684a568b3173ae13b9f8a6016e243e63b6e8ee1178d6a717850b5d6103;
                        /**
                         * @notice An event that is emitted each time the implementation is changed. This event is part
                         *         of the EIP-1967 specification.
                         *
                         * @param implementation The address of the implementation contract
                         */
                        event Upgraded(address indexed implementation);
                        /**
                         * @notice An event that is emitted each time the owner is upgraded. This event is part of the
                         *         EIP-1967 specification.
                         *
                         * @param previousAdmin The previous owner of the contract
                         * @param newAdmin      The new owner of the contract
                         */
                        event AdminChanged(address previousAdmin, address newAdmin);
                        /**
                         * @notice A modifier that reverts if not called by the owner or by address(0) to allow
                         *         eth_call to interact with this proxy without needing to use low-level storage
                         *         inspection. We assume that nobody is able to trigger calls from address(0) during
                         *         normal EVM execution.
                         */
                        modifier proxyCallIfNotAdmin() {
                            if (msg.sender == _getAdmin() || msg.sender == address(0)) {
                                _;
                            } else {
                                // This WILL halt the call frame on completion.
                                _doProxyCall();
                            }
                        }
                        /**
                         * @notice Sets the initial admin during contract deployment. Admin address is stored at the
                         *         EIP-1967 admin storage slot so that accidental storage collision with the
                         *         implementation is not possible.
                         *
                         * @param _admin Address of the initial contract admin. Admin as the ability to access the
                         *               transparent proxy interface.
                         */
                        constructor(address _admin) {
                            _changeAdmin(_admin);
                        }
                        // slither-disable-next-line locked-ether
                        receive() external payable {
                            // Proxy call by default.
                            _doProxyCall();
                        }
                        // slither-disable-next-line locked-ether
                        fallback() external payable {
                            // Proxy call by default.
                            _doProxyCall();
                        }
                        /**
                         * @notice Set the implementation contract address. The code at the given address will execute
                         *         when this contract is called.
                         *
                         * @param _implementation Address of the implementation contract.
                         */
                        function upgradeTo(address _implementation) public virtual proxyCallIfNotAdmin {
                            _setImplementation(_implementation);
                        }
                        /**
                         * @notice Set the implementation and call a function in a single transaction. Useful to ensure
                         *         atomic execution of initialization-based upgrades.
                         *
                         * @param _implementation Address of the implementation contract.
                         * @param _data           Calldata to delegatecall the new implementation with.
                         */
                        function upgradeToAndCall(address _implementation, bytes calldata _data)
                            public
                            payable
                            virtual
                            proxyCallIfNotAdmin
                            returns (bytes memory)
                        {
                            _setImplementation(_implementation);
                            (bool success, bytes memory returndata) = _implementation.delegatecall(_data);
                            require(success, "Proxy: delegatecall to new implementation contract failed");
                            return returndata;
                        }
                        /**
                         * @notice Changes the owner of the proxy contract. Only callable by the owner.
                         *
                         * @param _admin New owner of the proxy contract.
                         */
                        function changeAdmin(address _admin) public virtual proxyCallIfNotAdmin {
                            _changeAdmin(_admin);
                        }
                        /**
                         * @notice Gets the owner of the proxy contract.
                         *
                         * @return Owner address.
                         */
                        function admin() public virtual proxyCallIfNotAdmin returns (address) {
                            return _getAdmin();
                        }
                        /**
                         * @notice Queries the implementation address.
                         *
                         * @return Implementation address.
                         */
                        function implementation() public virtual proxyCallIfNotAdmin returns (address) {
                            return _getImplementation();
                        }
                        /**
                         * @notice Sets the implementation address.
                         *
                         * @param _implementation New implementation address.
                         */
                        function _setImplementation(address _implementation) internal {
                            assembly {
                                sstore(IMPLEMENTATION_KEY, _implementation)
                            }
                            emit Upgraded(_implementation);
                        }
                        /**
                         * @notice Changes the owner of the proxy contract.
                         *
                         * @param _admin New owner of the proxy contract.
                         */
                        function _changeAdmin(address _admin) internal {
                            address previous = _getAdmin();
                            assembly {
                                sstore(OWNER_KEY, _admin)
                            }
                            emit AdminChanged(previous, _admin);
                        }
                        /**
                         * @notice Performs the proxy call via a delegatecall.
                         */
                        function _doProxyCall() internal {
                            address impl = _getImplementation();
                            require(impl != address(0), "Proxy: implementation not initialized");
                            assembly {
                                // Copy calldata into memory at 0x0....calldatasize.
                                calldatacopy(0x0, 0x0, calldatasize())
                                // Perform the delegatecall, make sure to pass all available gas.
                                let success := delegatecall(gas(), impl, 0x0, calldatasize(), 0x0, 0x0)
                                // Copy returndata into memory at 0x0....returndatasize. Note that this *will*
                                // overwrite the calldata that we just copied into memory but that doesn't really
                                // matter because we'll be returning in a second anyway.
                                returndatacopy(0x0, 0x0, returndatasize())
                                // Success == 0 means a revert. We'll revert too and pass the data up.
                                if iszero(success) {
                                    revert(0x0, returndatasize())
                                }
                                // Otherwise we'll just return and pass the data up.
                                return(0x0, returndatasize())
                            }
                        }
                        /**
                         * @notice Queries the implementation address.
                         *
                         * @return Implementation address.
                         */
                        function _getImplementation() internal view returns (address) {
                            address impl;
                            assembly {
                                impl := sload(IMPLEMENTATION_KEY)
                            }
                            return impl;
                        }
                        /**
                         * @notice Queries the owner of the proxy contract.
                         *
                         * @return Owner address.
                         */
                        function _getAdmin() internal view returns (address) {
                            address owner;
                            assembly {
                                owner := sload(OWNER_KEY)
                            }
                            return owner;
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    pragma solidity 0.8.15;
                    import { Ownable } from "@openzeppelin/contracts/access/Ownable.sol";
                    import { Proxy } from "./Proxy.sol";
                    import { AddressManager } from "../legacy/AddressManager.sol";
                    import { L1ChugSplashProxy } from "../legacy/L1ChugSplashProxy.sol";
                    /**
                     * @title IStaticERC1967Proxy
                     * @notice IStaticERC1967Proxy is a static version of the ERC1967 proxy interface.
                     */
                    interface IStaticERC1967Proxy {
                        function implementation() external view returns (address);
                        function admin() external view returns (address);
                    }
                    /**
                     * @title IStaticL1ChugSplashProxy
                     * @notice IStaticL1ChugSplashProxy is a static version of the ChugSplash proxy interface.
                     */
                    interface IStaticL1ChugSplashProxy {
                        function getImplementation() external view returns (address);
                        function getOwner() external view returns (address);
                    }
                    /**
                     * @title ProxyAdmin
                     * @notice This is an auxiliary contract meant to be assigned as the admin of an ERC1967 Proxy,
                     *         based on the OpenZeppelin implementation. It has backwards compatibility logic to work
                     *         with the various types of proxies that have been deployed by Optimism in the past.
                     */
                    contract ProxyAdmin is Ownable {
                        /**
                         * @notice The proxy types that the ProxyAdmin can manage.
                         *
                         * @custom:value ERC1967    Represents an ERC1967 compliant transparent proxy interface.
                         * @custom:value CHUGSPLASH Represents the Chugsplash proxy interface (legacy).
                         * @custom:value RESOLVED   Represents the ResolvedDelegate proxy (legacy).
                         */
                        enum ProxyType {
                            ERC1967,
                            CHUGSPLASH,
                            RESOLVED
                        }
                        /**
                         * @notice A mapping of proxy types, used for backwards compatibility.
                         */
                        mapping(address => ProxyType) public proxyType;
                        /**
                         * @notice A reverse mapping of addresses to names held in the AddressManager. This must be
                         *         manually kept up to date with changes in the AddressManager for this contract
                         *         to be able to work as an admin for the ResolvedDelegateProxy type.
                         */
                        mapping(address => string) public implementationName;
                        /**
                         * @notice The address of the address manager, this is required to manage the
                         *         ResolvedDelegateProxy type.
                         */
                        AddressManager public addressManager;
                        /**
                         * @notice A legacy upgrading indicator used by the old Chugsplash Proxy.
                         */
                        bool internal upgrading;
                        /**
                         * @param _owner Address of the initial owner of this contract.
                         */
                        constructor(address _owner) Ownable() {
                            _transferOwnership(_owner);
                        }
                        /**
                         * @notice Sets the proxy type for a given address. Only required for non-standard (legacy)
                         *         proxy types.
                         *
                         * @param _address Address of the proxy.
                         * @param _type    Type of the proxy.
                         */
                        function setProxyType(address _address, ProxyType _type) external onlyOwner {
                            proxyType[_address] = _type;
                        }
                        /**
                         * @notice Sets the implementation name for a given address. Only required for
                         *         ResolvedDelegateProxy type proxies that have an implementation name.
                         *
                         * @param _address Address of the ResolvedDelegateProxy.
                         * @param _name    Name of the implementation for the proxy.
                         */
                        function setImplementationName(address _address, string memory _name) external onlyOwner {
                            implementationName[_address] = _name;
                        }
                        /**
                         * @notice Set the address of the AddressManager. This is required to manage legacy
                         *         ResolvedDelegateProxy type proxy contracts.
                         *
                         * @param _address Address of the AddressManager.
                         */
                        function setAddressManager(AddressManager _address) external onlyOwner {
                            addressManager = _address;
                        }
                        /**
                         * @custom:legacy
                         * @notice Set an address in the address manager. Since only the owner of the AddressManager
                         *         can directly modify addresses and the ProxyAdmin will own the AddressManager, this
                         *         gives the owner of the ProxyAdmin the ability to modify addresses directly.
                         *
                         * @param _name    Name to set within the AddressManager.
                         * @param _address Address to attach to the given name.
                         */
                        function setAddress(string memory _name, address _address) external onlyOwner {
                            addressManager.setAddress(_name, _address);
                        }
                        /**
                         * @custom:legacy
                         * @notice Set the upgrading status for the Chugsplash proxy type.
                         *
                         * @param _upgrading Whether or not the system is upgrading.
                         */
                        function setUpgrading(bool _upgrading) external onlyOwner {
                            upgrading = _upgrading;
                        }
                        /**
                         * @custom:legacy
                         * @notice Legacy function used to tell ChugSplashProxy contracts if an upgrade is happening.
                         *
                         * @return Whether or not there is an upgrade going on. May not actually tell you whether an
                         *         upgrade is going on, since we don't currently plan to use this variable for anything
                         *         other than a legacy indicator to fix a UX bug in the ChugSplash proxy.
                         */
                        function isUpgrading() external view returns (bool) {
                            return upgrading;
                        }
                        /**
                         * @notice Returns the implementation of the given proxy address.
                         *
                         * @param _proxy Address of the proxy to get the implementation of.
                         *
                         * @return Address of the implementation of the proxy.
                         */
                        function getProxyImplementation(address _proxy) external view returns (address) {
                            ProxyType ptype = proxyType[_proxy];
                            if (ptype == ProxyType.ERC1967) {
                                return IStaticERC1967Proxy(_proxy).implementation();
                            } else if (ptype == ProxyType.CHUGSPLASH) {
                                return IStaticL1ChugSplashProxy(_proxy).getImplementation();
                            } else if (ptype == ProxyType.RESOLVED) {
                                return addressManager.getAddress(implementationName[_proxy]);
                            } else {
                                revert("ProxyAdmin: unknown proxy type");
                            }
                        }
                        /**
                         * @notice Returns the admin of the given proxy address.
                         *
                         * @param _proxy Address of the proxy to get the admin of.
                         *
                         * @return Address of the admin of the proxy.
                         */
                        function getProxyAdmin(address payable _proxy) external view returns (address) {
                            ProxyType ptype = proxyType[_proxy];
                            if (ptype == ProxyType.ERC1967) {
                                return IStaticERC1967Proxy(_proxy).admin();
                            } else if (ptype == ProxyType.CHUGSPLASH) {
                                return IStaticL1ChugSplashProxy(_proxy).getOwner();
                            } else if (ptype == ProxyType.RESOLVED) {
                                return addressManager.owner();
                            } else {
                                revert("ProxyAdmin: unknown proxy type");
                            }
                        }
                        /**
                         * @notice Updates the admin of the given proxy address.
                         *
                         * @param _proxy    Address of the proxy to update.
                         * @param _newAdmin Address of the new proxy admin.
                         */
                        function changeProxyAdmin(address payable _proxy, address _newAdmin) external onlyOwner {
                            ProxyType ptype = proxyType[_proxy];
                            if (ptype == ProxyType.ERC1967) {
                                Proxy(_proxy).changeAdmin(_newAdmin);
                            } else if (ptype == ProxyType.CHUGSPLASH) {
                                L1ChugSplashProxy(_proxy).setOwner(_newAdmin);
                            } else if (ptype == ProxyType.RESOLVED) {
                                addressManager.transferOwnership(_newAdmin);
                            } else {
                                revert("ProxyAdmin: unknown proxy type");
                            }
                        }
                        /**
                         * @notice Changes a proxy's implementation contract.
                         *
                         * @param _proxy          Address of the proxy to upgrade.
                         * @param _implementation Address of the new implementation address.
                         */
                        function upgrade(address payable _proxy, address _implementation) public onlyOwner {
                            ProxyType ptype = proxyType[_proxy];
                            if (ptype == ProxyType.ERC1967) {
                                Proxy(_proxy).upgradeTo(_implementation);
                            } else if (ptype == ProxyType.CHUGSPLASH) {
                                L1ChugSplashProxy(_proxy).setStorage(
                                    // bytes32(uint256(keccak256('eip1967.proxy.implementation')) - 1)
                                    0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc,
                                    bytes32(uint256(uint160(_implementation)))
                                );
                            } else if (ptype == ProxyType.RESOLVED) {
                                string memory name = implementationName[_proxy];
                                addressManager.setAddress(name, _implementation);
                            } else {
                                // It should not be possible to retrieve a ProxyType value which is not matched by
                                // one of the previous conditions.
                                assert(false);
                            }
                        }
                        /**
                         * @notice Changes a proxy's implementation contract and delegatecalls the new implementation
                         *         with some given data. Useful for atomic upgrade-and-initialize calls.
                         *
                         * @param _proxy          Address of the proxy to upgrade.
                         * @param _implementation Address of the new implementation address.
                         * @param _data           Data to trigger the new implementation with.
                         */
                        function upgradeAndCall(
                            address payable _proxy,
                            address _implementation,
                            bytes memory _data
                        ) external payable onlyOwner {
                            ProxyType ptype = proxyType[_proxy];
                            if (ptype == ProxyType.ERC1967) {
                                Proxy(_proxy).upgradeToAndCall{ value: msg.value }(_implementation, _data);
                            } else {
                                // reverts if proxy type is unknown
                                upgrade(_proxy, _implementation);
                                (bool success, ) = _proxy.call{ value: msg.value }(_data);
                                require(success, "ProxyAdmin: call to proxy after upgrade failed");
                            }
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    // OpenZeppelin Contracts (last updated v4.7.0) (access/Ownable.sol)
                    pragma solidity ^0.8.0;
                    import "../utils/Context.sol";
                    /**
                     * @dev Contract module which provides a basic access control mechanism, where
                     * there is an account (an owner) that can be granted exclusive access to
                     * specific functions.
                     *
                     * By default, the owner account will be the one that deploys the contract. This
                     * can later be changed with {transferOwnership}.
                     *
                     * This module is used through inheritance. It will make available the modifier
                     * `onlyOwner`, which can be applied to your functions to restrict their use to
                     * the owner.
                     */
                    abstract contract Ownable is Context {
                        address private _owner;
                        event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
                        /**
                         * @dev Initializes the contract setting the deployer as the initial owner.
                         */
                        constructor() {
                            _transferOwnership(_msgSender());
                        }
                        /**
                         * @dev Throws if called by any account other than the owner.
                         */
                        modifier onlyOwner() {
                            _checkOwner();
                            _;
                        }
                        /**
                         * @dev Returns the address of the current owner.
                         */
                        function owner() public view virtual returns (address) {
                            return _owner;
                        }
                        /**
                         * @dev Throws if the sender is not the owner.
                         */
                        function _checkOwner() internal view virtual {
                            require(owner() == _msgSender(), "Ownable: caller is not the owner");
                        }
                        /**
                         * @dev Leaves the contract without owner. It will not be possible to call
                         * `onlyOwner` functions anymore. Can only be called by the current owner.
                         *
                         * NOTE: Renouncing ownership will leave the contract without an owner,
                         * thereby removing any functionality that is only available to the owner.
                         */
                        function renounceOwnership() public virtual onlyOwner {
                            _transferOwnership(address(0));
                        }
                        /**
                         * @dev Transfers ownership of the contract to a new account (`newOwner`).
                         * Can only be called by the current owner.
                         */
                        function transferOwnership(address newOwner) public virtual onlyOwner {
                            require(newOwner != address(0), "Ownable: new owner is the zero address");
                            _transferOwnership(newOwner);
                        }
                        /**
                         * @dev Transfers ownership of the contract to a new account (`newOwner`).
                         * Internal function without access restriction.
                         */
                        function _transferOwnership(address newOwner) internal virtual {
                            address oldOwner = _owner;
                            _owner = newOwner;
                            emit OwnershipTransferred(oldOwner, newOwner);
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    // OpenZeppelin Contracts v4.4.1 (utils/Context.sol)
                    pragma solidity ^0.8.0;
                    /**
                     * @dev Provides information about the current execution context, including the
                     * sender of the transaction and its data. While these are generally available
                     * via msg.sender and msg.data, they should not be accessed in such a direct
                     * manner, since when dealing with meta-transactions the account sending and
                     * paying for execution may not be the actual sender (as far as an application
                     * is concerned).
                     *
                     * This contract is only required for intermediate, library-like contracts.
                     */
                    abstract contract Context {
                        function _msgSender() internal view virtual returns (address) {
                            return msg.sender;
                        }
                        function _msgData() internal view virtual returns (bytes calldata) {
                            return msg.data;
                        }
                    }
                    

                    File 6 of 11: L1StandardBridge
                    // SPDX-License-Identifier: MIT
                    pragma solidity 0.8.15;
                    import { Predeploys } from "../libraries/Predeploys.sol";
                    import { StandardBridge } from "../universal/StandardBridge.sol";
                    import { Semver } from "../universal/Semver.sol";
                    /**
                     * @custom:proxied
                     * @title L1StandardBridge
                     * @notice The L1StandardBridge is responsible for transfering ETH and ERC20 tokens between L1 and
                     *         L2. In the case that an ERC20 token is native to L1, it will be escrowed within this
                     *         contract. If the ERC20 token is native to L2, it will be burnt. Before Bedrock, ETH was
                     *         stored within this contract. After Bedrock, ETH is instead stored inside the
                     *         OptimismPortal contract.
                     *         NOTE: this contract is not intended to support all variations of ERC20 tokens. Examples
                     *         of some token types that may not be properly supported by this contract include, but are
                     *         not limited to: tokens with transfer fees, rebasing tokens, and tokens with blocklists.
                     */
                    contract L1StandardBridge is StandardBridge, Semver {
                        /**
                         * @custom:legacy
                         * @notice Emitted whenever a deposit of ETH from L1 into L2 is initiated.
                         *
                         * @param from      Address of the depositor.
                         * @param to        Address of the recipient on L2.
                         * @param amount    Amount of ETH deposited.
                         * @param extraData Extra data attached to the deposit.
                         */
                        event ETHDepositInitiated(
                            address indexed from,
                            address indexed to,
                            uint256 amount,
                            bytes extraData
                        );
                        /**
                         * @custom:legacy
                         * @notice Emitted whenever a withdrawal of ETH from L2 to L1 is finalized.
                         *
                         * @param from      Address of the withdrawer.
                         * @param to        Address of the recipient on L1.
                         * @param amount    Amount of ETH withdrawn.
                         * @param extraData Extra data attached to the withdrawal.
                         */
                        event ETHWithdrawalFinalized(
                            address indexed from,
                            address indexed to,
                            uint256 amount,
                            bytes extraData
                        );
                        /**
                         * @custom:legacy
                         * @notice Emitted whenever an ERC20 deposit is initiated.
                         *
                         * @param l1Token   Address of the token on L1.
                         * @param l2Token   Address of the corresponding token on L2.
                         * @param from      Address of the depositor.
                         * @param to        Address of the recipient on L2.
                         * @param amount    Amount of the ERC20 deposited.
                         * @param extraData Extra data attached to the deposit.
                         */
                        event ERC20DepositInitiated(
                            address indexed l1Token,
                            address indexed l2Token,
                            address indexed from,
                            address to,
                            uint256 amount,
                            bytes extraData
                        );
                        /**
                         * @custom:legacy
                         * @notice Emitted whenever an ERC20 withdrawal is finalized.
                         *
                         * @param l1Token   Address of the token on L1.
                         * @param l2Token   Address of the corresponding token on L2.
                         * @param from      Address of the withdrawer.
                         * @param to        Address of the recipient on L1.
                         * @param amount    Amount of the ERC20 withdrawn.
                         * @param extraData Extra data attached to the withdrawal.
                         */
                        event ERC20WithdrawalFinalized(
                            address indexed l1Token,
                            address indexed l2Token,
                            address indexed from,
                            address to,
                            uint256 amount,
                            bytes extraData
                        );
                        /**
                         * @custom:semver 1.1.0
                         *
                         * @param _messenger Address of the L1CrossDomainMessenger.
                         */
                        constructor(address payable _messenger)
                            Semver(1, 1, 0)
                            StandardBridge(_messenger, payable(Predeploys.L2_STANDARD_BRIDGE))
                        {}
                        /**
                         * @notice Allows EOAs to bridge ETH by sending directly to the bridge.
                         */
                        receive() external payable override onlyEOA {
                            _initiateETHDeposit(msg.sender, msg.sender, RECEIVE_DEFAULT_GAS_LIMIT, bytes(""));
                        }
                        /**
                         * @custom:legacy
                         * @notice Deposits some amount of ETH into the sender's account on L2.
                         *
                         * @param _minGasLimit Minimum gas limit for the deposit message on L2.
                         * @param _extraData   Optional data to forward to L2. Data supplied here will not be used to
                         *                     execute any code on L2 and is only emitted as extra data for the
                         *                     convenience of off-chain tooling.
                         */
                        function depositETH(uint32 _minGasLimit, bytes calldata _extraData) external payable onlyEOA {
                            _initiateETHDeposit(msg.sender, msg.sender, _minGasLimit, _extraData);
                        }
                        /**
                         * @custom:legacy
                         * @notice Deposits some amount of ETH into a target account on L2.
                         *         Note that if ETH is sent to a contract on L2 and the call fails, then that ETH will
                         *         be locked in the L2StandardBridge. ETH may be recoverable if the call can be
                         *         successfully replayed by increasing the amount of gas supplied to the call. If the
                         *         call will fail for any amount of gas, then the ETH will be locked permanently.
                         *
                         * @param _to          Address of the recipient on L2.
                         * @param _minGasLimit Minimum gas limit for the deposit message on L2.
                         * @param _extraData   Optional data to forward to L2. Data supplied here will not be used to
                         *                     execute any code on L2 and is only emitted as extra data for the
                         *                     convenience of off-chain tooling.
                         */
                        function depositETHTo(
                            address _to,
                            uint32 _minGasLimit,
                            bytes calldata _extraData
                        ) external payable {
                            _initiateETHDeposit(msg.sender, _to, _minGasLimit, _extraData);
                        }
                        /**
                         * @custom:legacy
                         * @notice Deposits some amount of ERC20 tokens into the sender's account on L2.
                         *
                         * @param _l1Token     Address of the L1 token being deposited.
                         * @param _l2Token     Address of the corresponding token on L2.
                         * @param _amount      Amount of the ERC20 to deposit.
                         * @param _minGasLimit Minimum gas limit for the deposit message on L2.
                         * @param _extraData   Optional data to forward to L2. Data supplied here will not be used to
                         *                     execute any code on L2 and is only emitted as extra data for the
                         *                     convenience of off-chain tooling.
                         */
                        function depositERC20(
                            address _l1Token,
                            address _l2Token,
                            uint256 _amount,
                            uint32 _minGasLimit,
                            bytes calldata _extraData
                        ) external virtual onlyEOA {
                            _initiateERC20Deposit(
                                _l1Token,
                                _l2Token,
                                msg.sender,
                                msg.sender,
                                _amount,
                                _minGasLimit,
                                _extraData
                            );
                        }
                        /**
                         * @custom:legacy
                         * @notice Deposits some amount of ERC20 tokens into a target account on L2.
                         *
                         * @param _l1Token     Address of the L1 token being deposited.
                         * @param _l2Token     Address of the corresponding token on L2.
                         * @param _to          Address of the recipient on L2.
                         * @param _amount      Amount of the ERC20 to deposit.
                         * @param _minGasLimit Minimum gas limit for the deposit message on L2.
                         * @param _extraData   Optional data to forward to L2. Data supplied here will not be used to
                         *                     execute any code on L2 and is only emitted as extra data for the
                         *                     convenience of off-chain tooling.
                         */
                        function depositERC20To(
                            address _l1Token,
                            address _l2Token,
                            address _to,
                            uint256 _amount,
                            uint32 _minGasLimit,
                            bytes calldata _extraData
                        ) external virtual {
                            _initiateERC20Deposit(
                                _l1Token,
                                _l2Token,
                                msg.sender,
                                _to,
                                _amount,
                                _minGasLimit,
                                _extraData
                            );
                        }
                        /**
                         * @custom:legacy
                         * @notice Finalizes a withdrawal of ETH from L2.
                         *
                         * @param _from      Address of the withdrawer on L2.
                         * @param _to        Address of the recipient on L1.
                         * @param _amount    Amount of ETH to withdraw.
                         * @param _extraData Optional data forwarded from L2.
                         */
                        function finalizeETHWithdrawal(
                            address _from,
                            address _to,
                            uint256 _amount,
                            bytes calldata _extraData
                        ) external payable {
                            finalizeBridgeETH(_from, _to, _amount, _extraData);
                        }
                        /**
                         * @custom:legacy
                         * @notice Finalizes a withdrawal of ERC20 tokens from L2.
                         *
                         * @param _l1Token   Address of the token on L1.
                         * @param _l2Token   Address of the corresponding token on L2.
                         * @param _from      Address of the withdrawer on L2.
                         * @param _to        Address of the recipient on L1.
                         * @param _amount    Amount of the ERC20 to withdraw.
                         * @param _extraData Optional data forwarded from L2.
                         */
                        function finalizeERC20Withdrawal(
                            address _l1Token,
                            address _l2Token,
                            address _from,
                            address _to,
                            uint256 _amount,
                            bytes calldata _extraData
                        ) external {
                            finalizeBridgeERC20(_l1Token, _l2Token, _from, _to, _amount, _extraData);
                        }
                        /**
                         * @custom:legacy
                         * @notice Retrieves the access of the corresponding L2 bridge contract.
                         *
                         * @return Address of the corresponding L2 bridge contract.
                         */
                        function l2TokenBridge() external view returns (address) {
                            return address(OTHER_BRIDGE);
                        }
                        /**
                         * @notice Internal function for initiating an ETH deposit.
                         *
                         * @param _from        Address of the sender on L1.
                         * @param _to          Address of the recipient on L2.
                         * @param _minGasLimit Minimum gas limit for the deposit message on L2.
                         * @param _extraData   Optional data to forward to L2.
                         */
                        function _initiateETHDeposit(
                            address _from,
                            address _to,
                            uint32 _minGasLimit,
                            bytes memory _extraData
                        ) internal {
                            _initiateBridgeETH(_from, _to, msg.value, _minGasLimit, _extraData);
                        }
                        /**
                         * @notice Internal function for initiating an ERC20 deposit.
                         *
                         * @param _l1Token     Address of the L1 token being deposited.
                         * @param _l2Token     Address of the corresponding token on L2.
                         * @param _from        Address of the sender on L1.
                         * @param _to          Address of the recipient on L2.
                         * @param _amount      Amount of the ERC20 to deposit.
                         * @param _minGasLimit Minimum gas limit for the deposit message on L2.
                         * @param _extraData   Optional data to forward to L2.
                         */
                        function _initiateERC20Deposit(
                            address _l1Token,
                            address _l2Token,
                            address _from,
                            address _to,
                            uint256 _amount,
                            uint32 _minGasLimit,
                            bytes memory _extraData
                        ) internal {
                            _initiateBridgeERC20(_l1Token, _l2Token, _from, _to, _amount, _minGasLimit, _extraData);
                        }
                        /**
                         * @notice Emits the legacy ETHDepositInitiated event followed by the ETHBridgeInitiated event.
                         *         This is necessary for backwards compatibility with the legacy bridge.
                         *
                         * @inheritdoc StandardBridge
                         */
                        function _emitETHBridgeInitiated(
                            address _from,
                            address _to,
                            uint256 _amount,
                            bytes memory _extraData
                        ) internal override {
                            emit ETHDepositInitiated(_from, _to, _amount, _extraData);
                            super._emitETHBridgeInitiated(_from, _to, _amount, _extraData);
                        }
                        /**
                         * @notice Emits the legacy ETHWithdrawalFinalized event followed by the ETHBridgeFinalized
                         *         event. This is necessary for backwards compatibility with the legacy bridge.
                         *
                         * @inheritdoc StandardBridge
                         */
                        function _emitETHBridgeFinalized(
                            address _from,
                            address _to,
                            uint256 _amount,
                            bytes memory _extraData
                        ) internal override {
                            emit ETHWithdrawalFinalized(_from, _to, _amount, _extraData);
                            super._emitETHBridgeFinalized(_from, _to, _amount, _extraData);
                        }
                        /**
                         * @notice Emits the legacy ERC20DepositInitiated event followed by the ERC20BridgeInitiated
                         *         event. This is necessary for backwards compatibility with the legacy bridge.
                         *
                         * @inheritdoc StandardBridge
                         */
                        function _emitERC20BridgeInitiated(
                            address _localToken,
                            address _remoteToken,
                            address _from,
                            address _to,
                            uint256 _amount,
                            bytes memory _extraData
                        ) internal override {
                            emit ERC20DepositInitiated(_localToken, _remoteToken, _from, _to, _amount, _extraData);
                            super._emitERC20BridgeInitiated(_localToken, _remoteToken, _from, _to, _amount, _extraData);
                        }
                        /**
                         * @notice Emits the legacy ERC20WithdrawalFinalized event followed by the ERC20BridgeFinalized
                         *         event. This is necessary for backwards compatibility with the legacy bridge.
                         *
                         * @inheritdoc StandardBridge
                         */
                        function _emitERC20BridgeFinalized(
                            address _localToken,
                            address _remoteToken,
                            address _from,
                            address _to,
                            uint256 _amount,
                            bytes memory _extraData
                        ) internal override {
                            emit ERC20WithdrawalFinalized(_localToken, _remoteToken, _from, _to, _amount, _extraData);
                            super._emitERC20BridgeFinalized(_localToken, _remoteToken, _from, _to, _amount, _extraData);
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    pragma solidity 0.8.15;
                    import { Initializable } from "@openzeppelin/contracts/proxy/utils/Initializable.sol";
                    import { Math } from "@openzeppelin/contracts/utils/math/Math.sol";
                    import { Burn } from "../libraries/Burn.sol";
                    import { Arithmetic } from "../libraries/Arithmetic.sol";
                    /**
                     * @custom:upgradeable
                     * @title ResourceMetering
                     * @notice ResourceMetering implements an EIP-1559 style resource metering system where pricing
                     *         updates automatically based on current demand.
                     */
                    abstract contract ResourceMetering is Initializable {
                        /**
                         * @notice Represents the various parameters that control the way in which resources are
                         *         metered. Corresponds to the EIP-1559 resource metering system.
                         *
                         * @custom:field prevBaseFee   Base fee from the previous block(s).
                         * @custom:field prevBoughtGas Amount of gas bought so far in the current block.
                         * @custom:field prevBlockNum  Last block number that the base fee was updated.
                         */
                        struct ResourceParams {
                            uint128 prevBaseFee;
                            uint64 prevBoughtGas;
                            uint64 prevBlockNum;
                        }
                        /**
                         * @notice Represents the configuration for the EIP-1559 based curve for the deposit gas
                         *         market. These values should be set with care as it is possible to set them in
                         *         a way that breaks the deposit gas market. The target resource limit is defined as
                         *         maxResourceLimit / elasticityMultiplier. This struct was designed to fit within a
                         *         single word. There is additional space for additions in the future.
                         *
                         * @custom:field maxResourceLimit             Represents the maximum amount of deposit gas that
                         *                                            can be purchased per block.
                         * @custom:field elasticityMultiplier         Determines the target resource limit along with
                         *                                            the resource limit.
                         * @custom:field baseFeeMaxChangeDenominator  Determines max change on fee per block.
                         * @custom:field minimumBaseFee               The min deposit base fee, it is clamped to this
                         *                                            value.
                         * @custom:field systemTxMaxGas               The amount of gas supplied to the system
                         *                                            transaction. This should be set to the same number
                         *                                            that the op-node sets as the gas limit for the
                         *                                            system transaction.
                         * @custom:field maximumBaseFee               The max deposit base fee, it is clamped to this
                         *                                            value.
                         */
                        struct ResourceConfig {
                            uint32 maxResourceLimit;
                            uint8 elasticityMultiplier;
                            uint8 baseFeeMaxChangeDenominator;
                            uint32 minimumBaseFee;
                            uint32 systemTxMaxGas;
                            uint128 maximumBaseFee;
                        }
                        /**
                         * @notice EIP-1559 style gas parameters.
                         */
                        ResourceParams public params;
                        /**
                         * @notice Reserve extra slots (to a total of 50) in the storage layout for future upgrades.
                         */
                        uint256[48] private __gap;
                        /**
                         * @notice Meters access to a function based an amount of a requested resource.
                         *
                         * @param _amount Amount of the resource requested.
                         */
                        modifier metered(uint64 _amount) {
                            // Record initial gas amount so we can refund for it later.
                            uint256 initialGas = gasleft();
                            // Run the underlying function.
                            _;
                            // Run the metering function.
                            _metered(_amount, initialGas);
                        }
                        /**
                         * @notice An internal function that holds all of the logic for metering a resource.
                         *
                         * @param _amount     Amount of the resource requested.
                         * @param _initialGas The amount of gas before any modifier execution.
                         */
                        function _metered(uint64 _amount, uint256 _initialGas) internal {
                            // Update block number and base fee if necessary.
                            uint256 blockDiff = block.number - params.prevBlockNum;
                            ResourceConfig memory config = _resourceConfig();
                            int256 targetResourceLimit = int256(uint256(config.maxResourceLimit)) /
                                int256(uint256(config.elasticityMultiplier));
                            if (blockDiff > 0) {
                                // Handle updating EIP-1559 style gas parameters. We use EIP-1559 to restrict the rate
                                // at which deposits can be created and therefore limit the potential for deposits to
                                // spam the L2 system. Fee scheme is very similar to EIP-1559 with minor changes.
                                int256 gasUsedDelta = int256(uint256(params.prevBoughtGas)) - targetResourceLimit;
                                int256 baseFeeDelta = (int256(uint256(params.prevBaseFee)) * gasUsedDelta) /
                                    (targetResourceLimit * int256(uint256(config.baseFeeMaxChangeDenominator)));
                                // Update base fee by adding the base fee delta and clamp the resulting value between
                                // min and max.
                                int256 newBaseFee = Arithmetic.clamp({
                                    _value: int256(uint256(params.prevBaseFee)) + baseFeeDelta,
                                    _min: int256(uint256(config.minimumBaseFee)),
                                    _max: int256(uint256(config.maximumBaseFee))
                                });
                                // If we skipped more than one block, we also need to account for every empty block.
                                // Empty block means there was no demand for deposits in that block, so we should
                                // reflect this lack of demand in the fee.
                                if (blockDiff > 1) {
                                    // Update the base fee by repeatedly applying the exponent 1-(1/change_denominator)
                                    // blockDiff - 1 times. Simulates multiple empty blocks. Clamp the resulting value
                                    // between min and max.
                                    newBaseFee = Arithmetic.clamp({
                                        _value: Arithmetic.cdexp({
                                            _coefficient: newBaseFee,
                                            _denominator: int256(uint256(config.baseFeeMaxChangeDenominator)),
                                            _exponent: int256(blockDiff - 1)
                                        }),
                                        _min: int256(uint256(config.minimumBaseFee)),
                                        _max: int256(uint256(config.maximumBaseFee))
                                    });
                                }
                                // Update new base fee, reset bought gas, and update block number.
                                params.prevBaseFee = uint128(uint256(newBaseFee));
                                params.prevBoughtGas = 0;
                                params.prevBlockNum = uint64(block.number);
                            }
                            // Make sure we can actually buy the resource amount requested by the user.
                            params.prevBoughtGas += _amount;
                            require(
                                int256(uint256(params.prevBoughtGas)) <= int256(uint256(config.maxResourceLimit)),
                                "ResourceMetering: cannot buy more gas than available gas limit"
                            );
                            // Determine the amount of ETH to be paid.
                            uint256 resourceCost = uint256(_amount) * uint256(params.prevBaseFee);
                            // We currently charge for this ETH amount as an L1 gas burn, so we convert the ETH amount
                            // into gas by dividing by the L1 base fee. We assume a minimum base fee of 1 gwei to avoid
                            // division by zero for L1s that don't support 1559 or to avoid excessive gas burns during
                            // periods of extremely low L1 demand. One-day average gas fee hasn't dipped below 1 gwei
                            // during any 1 day period in the last 5 years, so should be fine.
                            uint256 gasCost = resourceCost / Math.max(block.basefee, 1 gwei);
                            // Give the user a refund based on the amount of gas they used to do all of the work up to
                            // this point. Since we're at the end of the modifier, this should be pretty accurate. Acts
                            // effectively like a dynamic stipend (with a minimum value).
                            uint256 usedGas = _initialGas - gasleft();
                            if (gasCost > usedGas) {
                                Burn.gas(gasCost - usedGas);
                            }
                        }
                        /**
                         * @notice Virtual function that returns the resource config. Contracts that inherit this
                         *         contract must implement this function.
                         *
                         * @return ResourceConfig
                         */
                        function _resourceConfig() internal virtual returns (ResourceConfig memory);
                        /**
                         * @notice Sets initial resource parameter values. This function must either be called by the
                         *         initializer function of an upgradeable child contract.
                         */
                        // solhint-disable-next-line func-name-mixedcase
                        function __ResourceMetering_init() internal onlyInitializing {
                            params = ResourceParams({
                                prevBaseFee: 1 gwei,
                                prevBoughtGas: 0,
                                prevBlockNum: uint64(block.number)
                            });
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    pragma solidity 0.8.15;
                    import { SignedMath } from "@openzeppelin/contracts/utils/math/SignedMath.sol";
                    import { FixedPointMathLib } from "@rari-capital/solmate/src/utils/FixedPointMathLib.sol";
                    /**
                     * @title Arithmetic
                     * @notice Even more math than before.
                     */
                    library Arithmetic {
                        /**
                         * @notice Clamps a value between a minimum and maximum.
                         *
                         * @param _value The value to clamp.
                         * @param _min   The minimum value.
                         * @param _max   The maximum value.
                         *
                         * @return The clamped value.
                         */
                        function clamp(
                            int256 _value,
                            int256 _min,
                            int256 _max
                        ) internal pure returns (int256) {
                            return SignedMath.min(SignedMath.max(_value, _min), _max);
                        }
                        /**
                         * @notice (c)oefficient (d)enominator (exp)onentiation function.
                         *         Returns the result of: c * (1 - 1/d)^exp.
                         *
                         * @param _coefficient Coefficient of the function.
                         * @param _denominator Fractional denominator.
                         * @param _exponent    Power function exponent.
                         *
                         * @return Result of c * (1 - 1/d)^exp.
                         */
                        function cdexp(
                            int256 _coefficient,
                            int256 _denominator,
                            int256 _exponent
                        ) internal pure returns (int256) {
                            return
                                (_coefficient *
                                    (FixedPointMathLib.powWad(1e18 - (1e18 / _denominator), _exponent * 1e18))) / 1e18;
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    pragma solidity 0.8.15;
                    /**
                     * @title Burn
                     * @notice Utilities for burning stuff.
                     */
                    library Burn {
                        /**
                         * Burns a given amount of ETH.
                         *
                         * @param _amount Amount of ETH to burn.
                         */
                        function eth(uint256 _amount) internal {
                            new Burner{ value: _amount }();
                        }
                        /**
                         * Burns a given amount of gas.
                         *
                         * @param _amount Amount of gas to burn.
                         */
                        function gas(uint256 _amount) internal view {
                            uint256 i = 0;
                            uint256 initialGas = gasleft();
                            while (initialGas - gasleft() < _amount) {
                                ++i;
                            }
                        }
                    }
                    /**
                     * @title Burner
                     * @notice Burner self-destructs on creation and sends all ETH to itself, removing all ETH given to
                     *         the contract from the circulating supply. Self-destructing is the only way to remove ETH
                     *         from the circulating supply.
                     */
                    contract Burner {
                        constructor() payable {
                            selfdestruct(payable(address(this)));
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    pragma solidity ^0.8.0;
                    import { ResourceMetering } from "../L1/ResourceMetering.sol";
                    /**
                     * @title Constants
                     * @notice Constants is a library for storing constants. Simple! Don't put everything in here, just
                     *         the stuff used in multiple contracts. Constants that only apply to a single contract
                     *         should be defined in that contract instead.
                     */
                    library Constants {
                        /**
                         * @notice Special address to be used as the tx origin for gas estimation calls in the
                         *         OptimismPortal and CrossDomainMessenger calls. You only need to use this address if
                         *         the minimum gas limit specified by the user is not actually enough to execute the
                         *         given message and you're attempting to estimate the actual necessary gas limit. We
                         *         use address(1) because it's the ecrecover precompile and therefore guaranteed to
                         *         never have any code on any EVM chain.
                         */
                        address internal constant ESTIMATION_ADDRESS = address(1);
                        /**
                         * @notice Value used for the L2 sender storage slot in both the OptimismPortal and the
                         *         CrossDomainMessenger contracts before an actual sender is set. This value is
                         *         non-zero to reduce the gas cost of message passing transactions.
                         */
                        address internal constant DEFAULT_L2_SENDER = 0x000000000000000000000000000000000000dEaD;
                        /**
                         * @notice Returns the default values for the ResourceConfig. These are the recommended values
                         *         for a production network.
                         */
                        function DEFAULT_RESOURCE_CONFIG()
                            internal
                            pure
                            returns (ResourceMetering.ResourceConfig memory)
                        {
                            ResourceMetering.ResourceConfig memory config = ResourceMetering.ResourceConfig({
                                maxResourceLimit: 20_000_000,
                                elasticityMultiplier: 10,
                                baseFeeMaxChangeDenominator: 8,
                                minimumBaseFee: 1 gwei,
                                systemTxMaxGas: 1_000_000,
                                maximumBaseFee: type(uint128).max
                            });
                            return config;
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    pragma solidity ^0.8.0;
                    import { Types } from "./Types.sol";
                    import { Hashing } from "./Hashing.sol";
                    import { RLPWriter } from "./rlp/RLPWriter.sol";
                    /**
                     * @title Encoding
                     * @notice Encoding handles Optimism's various different encoding schemes.
                     */
                    library Encoding {
                        /**
                         * @notice RLP encodes the L2 transaction that would be generated when a given deposit is sent
                         *         to the L2 system. Useful for searching for a deposit in the L2 system. The
                         *         transaction is prefixed with 0x7e to identify its EIP-2718 type.
                         *
                         * @param _tx User deposit transaction to encode.
                         *
                         * @return RLP encoded L2 deposit transaction.
                         */
                        function encodeDepositTransaction(Types.UserDepositTransaction memory _tx)
                            internal
                            pure
                            returns (bytes memory)
                        {
                            bytes32 source = Hashing.hashDepositSource(_tx.l1BlockHash, _tx.logIndex);
                            bytes[] memory raw = new bytes[](8);
                            raw[0] = RLPWriter.writeBytes(abi.encodePacked(source));
                            raw[1] = RLPWriter.writeAddress(_tx.from);
                            raw[2] = _tx.isCreation ? RLPWriter.writeBytes("") : RLPWriter.writeAddress(_tx.to);
                            raw[3] = RLPWriter.writeUint(_tx.mint);
                            raw[4] = RLPWriter.writeUint(_tx.value);
                            raw[5] = RLPWriter.writeUint(uint256(_tx.gasLimit));
                            raw[6] = RLPWriter.writeBool(false);
                            raw[7] = RLPWriter.writeBytes(_tx.data);
                            return abi.encodePacked(uint8(0x7e), RLPWriter.writeList(raw));
                        }
                        /**
                         * @notice Encodes the cross domain message based on the version that is encoded into the
                         *         message nonce.
                         *
                         * @param _nonce    Message nonce with version encoded into the first two bytes.
                         * @param _sender   Address of the sender of the message.
                         * @param _target   Address of the target of the message.
                         * @param _value    ETH value to send to the target.
                         * @param _gasLimit Gas limit to use for the message.
                         * @param _data     Data to send with the message.
                         *
                         * @return Encoded cross domain message.
                         */
                        function encodeCrossDomainMessage(
                            uint256 _nonce,
                            address _sender,
                            address _target,
                            uint256 _value,
                            uint256 _gasLimit,
                            bytes memory _data
                        ) internal pure returns (bytes memory) {
                            (, uint16 version) = decodeVersionedNonce(_nonce);
                            if (version == 0) {
                                return encodeCrossDomainMessageV0(_target, _sender, _data, _nonce);
                            } else if (version == 1) {
                                return encodeCrossDomainMessageV1(_nonce, _sender, _target, _value, _gasLimit, _data);
                            } else {
                                revert("Encoding: unknown cross domain message version");
                            }
                        }
                        /**
                         * @notice Encodes a cross domain message based on the V0 (legacy) encoding.
                         *
                         * @param _target Address of the target of the message.
                         * @param _sender Address of the sender of the message.
                         * @param _data   Data to send with the message.
                         * @param _nonce  Message nonce.
                         *
                         * @return Encoded cross domain message.
                         */
                        function encodeCrossDomainMessageV0(
                            address _target,
                            address _sender,
                            bytes memory _data,
                            uint256 _nonce
                        ) internal pure returns (bytes memory) {
                            return
                                abi.encodeWithSignature(
                                    "relayMessage(address,address,bytes,uint256)",
                                    _target,
                                    _sender,
                                    _data,
                                    _nonce
                                );
                        }
                        /**
                         * @notice Encodes a cross domain message based on the V1 (current) encoding.
                         *
                         * @param _nonce    Message nonce.
                         * @param _sender   Address of the sender of the message.
                         * @param _target   Address of the target of the message.
                         * @param _value    ETH value to send to the target.
                         * @param _gasLimit Gas limit to use for the message.
                         * @param _data     Data to send with the message.
                         *
                         * @return Encoded cross domain message.
                         */
                        function encodeCrossDomainMessageV1(
                            uint256 _nonce,
                            address _sender,
                            address _target,
                            uint256 _value,
                            uint256 _gasLimit,
                            bytes memory _data
                        ) internal pure returns (bytes memory) {
                            return
                                abi.encodeWithSignature(
                                    "relayMessage(uint256,address,address,uint256,uint256,bytes)",
                                    _nonce,
                                    _sender,
                                    _target,
                                    _value,
                                    _gasLimit,
                                    _data
                                );
                        }
                        /**
                         * @notice Adds a version number into the first two bytes of a message nonce.
                         *
                         * @param _nonce   Message nonce to encode into.
                         * @param _version Version number to encode into the message nonce.
                         *
                         * @return Message nonce with version encoded into the first two bytes.
                         */
                        function encodeVersionedNonce(uint240 _nonce, uint16 _version) internal pure returns (uint256) {
                            uint256 nonce;
                            assembly {
                                nonce := or(shl(240, _version), _nonce)
                            }
                            return nonce;
                        }
                        /**
                         * @notice Pulls the version out of a version-encoded nonce.
                         *
                         * @param _nonce Message nonce with version encoded into the first two bytes.
                         *
                         * @return Nonce without encoded version.
                         * @return Version of the message.
                         */
                        function decodeVersionedNonce(uint256 _nonce) internal pure returns (uint240, uint16) {
                            uint240 nonce;
                            uint16 version;
                            assembly {
                                nonce := and(_nonce, 0x0000ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff)
                                version := shr(240, _nonce)
                            }
                            return (nonce, version);
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    pragma solidity ^0.8.0;
                    import { Types } from "./Types.sol";
                    import { Encoding } from "./Encoding.sol";
                    /**
                     * @title Hashing
                     * @notice Hashing handles Optimism's various different hashing schemes.
                     */
                    library Hashing {
                        /**
                         * @notice Computes the hash of the RLP encoded L2 transaction that would be generated when a
                         *         given deposit is sent to the L2 system. Useful for searching for a deposit in the L2
                         *         system.
                         *
                         * @param _tx User deposit transaction to hash.
                         *
                         * @return Hash of the RLP encoded L2 deposit transaction.
                         */
                        function hashDepositTransaction(Types.UserDepositTransaction memory _tx)
                            internal
                            pure
                            returns (bytes32)
                        {
                            return keccak256(Encoding.encodeDepositTransaction(_tx));
                        }
                        /**
                         * @notice Computes the deposit transaction's "source hash", a value that guarantees the hash
                         *         of the L2 transaction that corresponds to a deposit is unique and is
                         *         deterministically generated from L1 transaction data.
                         *
                         * @param _l1BlockHash Hash of the L1 block where the deposit was included.
                         * @param _logIndex    The index of the log that created the deposit transaction.
                         *
                         * @return Hash of the deposit transaction's "source hash".
                         */
                        function hashDepositSource(bytes32 _l1BlockHash, uint256 _logIndex)
                            internal
                            pure
                            returns (bytes32)
                        {
                            bytes32 depositId = keccak256(abi.encode(_l1BlockHash, _logIndex));
                            return keccak256(abi.encode(bytes32(0), depositId));
                        }
                        /**
                         * @notice Hashes the cross domain message based on the version that is encoded into the
                         *         message nonce.
                         *
                         * @param _nonce    Message nonce with version encoded into the first two bytes.
                         * @param _sender   Address of the sender of the message.
                         * @param _target   Address of the target of the message.
                         * @param _value    ETH value to send to the target.
                         * @param _gasLimit Gas limit to use for the message.
                         * @param _data     Data to send with the message.
                         *
                         * @return Hashed cross domain message.
                         */
                        function hashCrossDomainMessage(
                            uint256 _nonce,
                            address _sender,
                            address _target,
                            uint256 _value,
                            uint256 _gasLimit,
                            bytes memory _data
                        ) internal pure returns (bytes32) {
                            (, uint16 version) = Encoding.decodeVersionedNonce(_nonce);
                            if (version == 0) {
                                return hashCrossDomainMessageV0(_target, _sender, _data, _nonce);
                            } else if (version == 1) {
                                return hashCrossDomainMessageV1(_nonce, _sender, _target, _value, _gasLimit, _data);
                            } else {
                                revert("Hashing: unknown cross domain message version");
                            }
                        }
                        /**
                         * @notice Hashes a cross domain message based on the V0 (legacy) encoding.
                         *
                         * @param _target Address of the target of the message.
                         * @param _sender Address of the sender of the message.
                         * @param _data   Data to send with the message.
                         * @param _nonce  Message nonce.
                         *
                         * @return Hashed cross domain message.
                         */
                        function hashCrossDomainMessageV0(
                            address _target,
                            address _sender,
                            bytes memory _data,
                            uint256 _nonce
                        ) internal pure returns (bytes32) {
                            return keccak256(Encoding.encodeCrossDomainMessageV0(_target, _sender, _data, _nonce));
                        }
                        /**
                         * @notice Hashes a cross domain message based on the V1 (current) encoding.
                         *
                         * @param _nonce    Message nonce.
                         * @param _sender   Address of the sender of the message.
                         * @param _target   Address of the target of the message.
                         * @param _value    ETH value to send to the target.
                         * @param _gasLimit Gas limit to use for the message.
                         * @param _data     Data to send with the message.
                         *
                         * @return Hashed cross domain message.
                         */
                        function hashCrossDomainMessageV1(
                            uint256 _nonce,
                            address _sender,
                            address _target,
                            uint256 _value,
                            uint256 _gasLimit,
                            bytes memory _data
                        ) internal pure returns (bytes32) {
                            return
                                keccak256(
                                    Encoding.encodeCrossDomainMessageV1(
                                        _nonce,
                                        _sender,
                                        _target,
                                        _value,
                                        _gasLimit,
                                        _data
                                    )
                                );
                        }
                        /**
                         * @notice Derives the withdrawal hash according to the encoding in the L2 Withdrawer contract
                         *
                         * @param _tx Withdrawal transaction to hash.
                         *
                         * @return Hashed withdrawal transaction.
                         */
                        function hashWithdrawal(Types.WithdrawalTransaction memory _tx)
                            internal
                            pure
                            returns (bytes32)
                        {
                            return
                                keccak256(
                                    abi.encode(_tx.nonce, _tx.sender, _tx.target, _tx.value, _tx.gasLimit, _tx.data)
                                );
                        }
                        /**
                         * @notice Hashes the various elements of an output root proof into an output root hash which
                         *         can be used to check if the proof is valid.
                         *
                         * @param _outputRootProof Output root proof which should hash to an output root.
                         *
                         * @return Hashed output root proof.
                         */
                        function hashOutputRootProof(Types.OutputRootProof memory _outputRootProof)
                            internal
                            pure
                            returns (bytes32)
                        {
                            return
                                keccak256(
                                    abi.encode(
                                        _outputRootProof.version,
                                        _outputRootProof.stateRoot,
                                        _outputRootProof.messagePasserStorageRoot,
                                        _outputRootProof.latestBlockhash
                                    )
                                );
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    pragma solidity ^0.8.0;
                    /**
                     * @title Predeploys
                     * @notice Contains constant addresses for contracts that are pre-deployed to the L2 system.
                     */
                    library Predeploys {
                        /**
                         * @notice Address of the L2ToL1MessagePasser predeploy.
                         */
                        address internal constant L2_TO_L1_MESSAGE_PASSER = 0x4200000000000000000000000000000000000016;
                        /**
                         * @notice Address of the L2CrossDomainMessenger predeploy.
                         */
                        address internal constant L2_CROSS_DOMAIN_MESSENGER =
                            0x4200000000000000000000000000000000000007;
                        /**
                         * @notice Address of the L2StandardBridge predeploy.
                         */
                        address internal constant L2_STANDARD_BRIDGE = 0x4200000000000000000000000000000000000010;
                        /**
                         * @notice Address of the L2ERC721Bridge predeploy.
                         */
                        address internal constant L2_ERC721_BRIDGE = 0x4200000000000000000000000000000000000014;
                        /**
                         * @notice Address of the SequencerFeeWallet predeploy.
                         */
                        address internal constant SEQUENCER_FEE_WALLET = 0x4200000000000000000000000000000000000011;
                        /**
                         * @notice Address of the OptimismMintableERC20Factory predeploy.
                         */
                        address internal constant OPTIMISM_MINTABLE_ERC20_FACTORY =
                            0x4200000000000000000000000000000000000012;
                        /**
                         * @notice Address of the OptimismMintableERC721Factory predeploy.
                         */
                        address internal constant OPTIMISM_MINTABLE_ERC721_FACTORY =
                            0x4200000000000000000000000000000000000017;
                        /**
                         * @notice Address of the L1Block predeploy.
                         */
                        address internal constant L1_BLOCK_ATTRIBUTES = 0x4200000000000000000000000000000000000015;
                        /**
                         * @notice Address of the GasPriceOracle predeploy. Includes fee information
                         *         and helpers for computing the L1 portion of the transaction fee.
                         */
                        address internal constant GAS_PRICE_ORACLE = 0x420000000000000000000000000000000000000F;
                        /**
                         * @custom:legacy
                         * @notice Address of the L1MessageSender predeploy. Deprecated. Use L2CrossDomainMessenger
                         *         or access tx.origin (or msg.sender) in a L1 to L2 transaction instead.
                         */
                        address internal constant L1_MESSAGE_SENDER = 0x4200000000000000000000000000000000000001;
                        /**
                         * @custom:legacy
                         * @notice Address of the DeployerWhitelist predeploy. No longer active.
                         */
                        address internal constant DEPLOYER_WHITELIST = 0x4200000000000000000000000000000000000002;
                        /**
                         * @custom:legacy
                         * @notice Address of the LegacyERC20ETH predeploy. Deprecated. Balances are migrated to the
                         *         state trie as of the Bedrock upgrade. Contract has been locked and write functions
                         *         can no longer be accessed.
                         */
                        address internal constant LEGACY_ERC20_ETH = 0xDeadDeAddeAddEAddeadDEaDDEAdDeaDDeAD0000;
                        /**
                         * @custom:legacy
                         * @notice Address of the L1BlockNumber predeploy. Deprecated. Use the L1Block predeploy
                         *         instead, which exposes more information about the L1 state.
                         */
                        address internal constant L1_BLOCK_NUMBER = 0x4200000000000000000000000000000000000013;
                        /**
                         * @custom:legacy
                         * @notice Address of the LegacyMessagePasser predeploy. Deprecate. Use the updated
                         *         L2ToL1MessagePasser contract instead.
                         */
                        address internal constant LEGACY_MESSAGE_PASSER = 0x4200000000000000000000000000000000000000;
                        /**
                         * @notice Address of the ProxyAdmin predeploy.
                         */
                        address internal constant PROXY_ADMIN = 0x4200000000000000000000000000000000000018;
                        /**
                         * @notice Address of the BaseFeeVault predeploy.
                         */
                        address internal constant BASE_FEE_VAULT = 0x4200000000000000000000000000000000000019;
                        /**
                         * @notice Address of the L1FeeVault predeploy.
                         */
                        address internal constant L1_FEE_VAULT = 0x420000000000000000000000000000000000001A;
                        /**
                         * @notice Address of the GovernanceToken predeploy.
                         */
                        address internal constant GOVERNANCE_TOKEN = 0x4200000000000000000000000000000000000042;
                    }
                    // SPDX-License-Identifier: MIT
                    pragma solidity 0.8.15;
                    /**
                     * @title SafeCall
                     * @notice Perform low level safe calls
                     */
                    library SafeCall {
                        /**
                         * @notice Perform a low level call without copying any returndata
                         *
                         * @param _target   Address to call
                         * @param _gas      Amount of gas to pass to the call
                         * @param _value    Amount of value to pass to the call
                         * @param _calldata Calldata to pass to the call
                         */
                        function call(
                            address _target,
                            uint256 _gas,
                            uint256 _value,
                            bytes memory _calldata
                        ) internal returns (bool) {
                            bool _success;
                            assembly {
                                _success := call(
                                    _gas, // gas
                                    _target, // recipient
                                    _value, // ether value
                                    add(_calldata, 32), // inloc
                                    mload(_calldata), // inlen
                                    0, // outloc
                                    0 // outlen
                                )
                            }
                            return _success;
                        }
                        /**
                         * @notice Perform a low level call without copying any returndata. This function
                         *         will revert if the call cannot be performed with the specified minimum
                         *         gas.
                         *
                         * @param _target   Address to call
                         * @param _minGas   The minimum amount of gas that may be passed to the call
                         * @param _value    Amount of value to pass to the call
                         * @param _calldata Calldata to pass to the call
                         */
                        function callWithMinGas(
                            address _target,
                            uint256 _minGas,
                            uint256 _value,
                            bytes memory _calldata
                        ) internal returns (bool) {
                            bool _success;
                            assembly {
                                // Assertion: gasleft() >= ((_minGas + 200) * 64) / 63
                                //
                                // Because EIP-150 ensures that, a maximum of 63/64ths of the remaining gas in the call
                                // frame may be passed to a subcontext, we need to ensure that the gas will not be
                                // truncated to hold this function's invariant: "If a call is performed by
                                // `callWithMinGas`, it must receive at least the specified minimum gas limit." In
                                // addition, exactly 51 gas is consumed between the below `GAS` opcode and the `CALL`
                                // opcode, so it is factored in with some extra room for error.
                                if lt(gas(), div(mul(64, add(_minGas, 200)), 63)) {
                                    // Store the "Error(string)" selector in scratch space.
                                    mstore(0, 0x08c379a0)
                                    // Store the pointer to the string length in scratch space.
                                    mstore(32, 32)
                                    // Store the string.
                                    //
                                    // SAFETY:
                                    // - We pad the beginning of the string with two zero bytes as well as the
                                    // length (24) to ensure that we override the free memory pointer at offset
                                    // 0x40. This is necessary because the free memory pointer is likely to
                                    // be greater than 1 byte when this function is called, but it is incredibly
                                    // unlikely that it will be greater than 3 bytes. As for the data within
                                    // 0x60, it is ensured that it is 0 due to 0x60 being the zero offset.
                                    // - It's fine to clobber the free memory pointer, we're reverting.
                                    mstore(88, 0x0000185361666543616c6c3a204e6f7420656e6f75676820676173)
                                    // Revert with 'Error("SafeCall: Not enough gas")'
                                    revert(28, 100)
                                }
                                // The call will be supplied at least (((_minGas + 200) * 64) / 63) - 49 gas due to the
                                // above assertion. This ensures that, in all circumstances, the call will
                                // receive at least the minimum amount of gas specified.
                                // We can prove this property by solving the inequalities:
                                // ((((_minGas + 200) * 64) / 63) - 49) >= _minGas
                                // ((((_minGas + 200) * 64) / 63) - 51) * (63 / 64) >= _minGas
                                // Both inequalities hold true for all possible values of `_minGas`.
                                _success := call(
                                    gas(), // gas
                                    _target, // recipient
                                    _value, // ether value
                                    add(_calldata, 32), // inloc
                                    mload(_calldata), // inlen
                                    0x00, // outloc
                                    0x00 // outlen
                                )
                            }
                            return _success;
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    pragma solidity ^0.8.0;
                    /**
                     * @title Types
                     * @notice Contains various types used throughout the Optimism contract system.
                     */
                    library Types {
                        /**
                         * @notice OutputProposal represents a commitment to the L2 state. The timestamp is the L1
                         *         timestamp that the output root is posted. This timestamp is used to verify that the
                         *         finalization period has passed since the output root was submitted.
                         *
                         * @custom:field outputRoot    Hash of the L2 output.
                         * @custom:field timestamp     Timestamp of the L1 block that the output root was submitted in.
                         * @custom:field l2BlockNumber L2 block number that the output corresponds to.
                         */
                        struct OutputProposal {
                            bytes32 outputRoot;
                            uint128 timestamp;
                            uint128 l2BlockNumber;
                        }
                        /**
                         * @notice Struct representing the elements that are hashed together to generate an output root
                         *         which itself represents a snapshot of the L2 state.
                         *
                         * @custom:field version                  Version of the output root.
                         * @custom:field stateRoot                Root of the state trie at the block of this output.
                         * @custom:field messagePasserStorageRoot Root of the message passer storage trie.
                         * @custom:field latestBlockhash          Hash of the block this output was generated from.
                         */
                        struct OutputRootProof {
                            bytes32 version;
                            bytes32 stateRoot;
                            bytes32 messagePasserStorageRoot;
                            bytes32 latestBlockhash;
                        }
                        /**
                         * @notice Struct representing a deposit transaction (L1 => L2 transaction) created by an end
                         *         user (as opposed to a system deposit transaction generated by the system).
                         *
                         * @custom:field from        Address of the sender of the transaction.
                         * @custom:field to          Address of the recipient of the transaction.
                         * @custom:field isCreation  True if the transaction is a contract creation.
                         * @custom:field value       Value to send to the recipient.
                         * @custom:field mint        Amount of ETH to mint.
                         * @custom:field gasLimit    Gas limit of the transaction.
                         * @custom:field data        Data of the transaction.
                         * @custom:field l1BlockHash Hash of the block the transaction was submitted in.
                         * @custom:field logIndex    Index of the log in the block the transaction was submitted in.
                         */
                        struct UserDepositTransaction {
                            address from;
                            address to;
                            bool isCreation;
                            uint256 value;
                            uint256 mint;
                            uint64 gasLimit;
                            bytes data;
                            bytes32 l1BlockHash;
                            uint256 logIndex;
                        }
                        /**
                         * @notice Struct representing a withdrawal transaction.
                         *
                         * @custom:field nonce    Nonce of the withdrawal transaction
                         * @custom:field sender   Address of the sender of the transaction.
                         * @custom:field target   Address of the recipient of the transaction.
                         * @custom:field value    Value to send to the recipient.
                         * @custom:field gasLimit Gas limit of the transaction.
                         * @custom:field data     Data of the transaction.
                         */
                        struct WithdrawalTransaction {
                            uint256 nonce;
                            address sender;
                            address target;
                            uint256 value;
                            uint256 gasLimit;
                            bytes data;
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    pragma solidity ^0.8.0;
                    /**
                     * @custom:attribution https://github.com/bakaoh/solidity-rlp-encode
                     * @title RLPWriter
                     * @author RLPWriter is a library for encoding Solidity types to RLP bytes. Adapted from Bakaoh's
                     *         RLPEncode library (https://github.com/bakaoh/solidity-rlp-encode) with minor
                     *         modifications to improve legibility.
                     */
                    library RLPWriter {
                        /**
                         * @notice RLP encodes a byte string.
                         *
                         * @param _in The byte string to encode.
                         *
                         * @return The RLP encoded string in bytes.
                         */
                        function writeBytes(bytes memory _in) internal pure returns (bytes memory) {
                            bytes memory encoded;
                            if (_in.length == 1 && uint8(_in[0]) < 128) {
                                encoded = _in;
                            } else {
                                encoded = abi.encodePacked(_writeLength(_in.length, 128), _in);
                            }
                            return encoded;
                        }
                        /**
                         * @notice RLP encodes a list of RLP encoded byte byte strings.
                         *
                         * @param _in The list of RLP encoded byte strings.
                         *
                         * @return The RLP encoded list of items in bytes.
                         */
                        function writeList(bytes[] memory _in) internal pure returns (bytes memory) {
                            bytes memory list = _flatten(_in);
                            return abi.encodePacked(_writeLength(list.length, 192), list);
                        }
                        /**
                         * @notice RLP encodes a string.
                         *
                         * @param _in The string to encode.
                         *
                         * @return The RLP encoded string in bytes.
                         */
                        function writeString(string memory _in) internal pure returns (bytes memory) {
                            return writeBytes(bytes(_in));
                        }
                        /**
                         * @notice RLP encodes an address.
                         *
                         * @param _in The address to encode.
                         *
                         * @return The RLP encoded address in bytes.
                         */
                        function writeAddress(address _in) internal pure returns (bytes memory) {
                            return writeBytes(abi.encodePacked(_in));
                        }
                        /**
                         * @notice RLP encodes a uint.
                         *
                         * @param _in The uint256 to encode.
                         *
                         * @return The RLP encoded uint256 in bytes.
                         */
                        function writeUint(uint256 _in) internal pure returns (bytes memory) {
                            return writeBytes(_toBinary(_in));
                        }
                        /**
                         * @notice RLP encodes a bool.
                         *
                         * @param _in The bool to encode.
                         *
                         * @return The RLP encoded bool in bytes.
                         */
                        function writeBool(bool _in) internal pure returns (bytes memory) {
                            bytes memory encoded = new bytes(1);
                            encoded[0] = (_in ? bytes1(0x01) : bytes1(0x80));
                            return encoded;
                        }
                        /**
                         * @notice Encode the first byte and then the `len` in binary form if `length` is more than 55.
                         *
                         * @param _len    The length of the string or the payload.
                         * @param _offset 128 if item is string, 192 if item is list.
                         *
                         * @return RLP encoded bytes.
                         */
                        function _writeLength(uint256 _len, uint256 _offset) private pure returns (bytes memory) {
                            bytes memory encoded;
                            if (_len < 56) {
                                encoded = new bytes(1);
                                encoded[0] = bytes1(uint8(_len) + uint8(_offset));
                            } else {
                                uint256 lenLen;
                                uint256 i = 1;
                                while (_len / i != 0) {
                                    lenLen++;
                                    i *= 256;
                                }
                                encoded = new bytes(lenLen + 1);
                                encoded[0] = bytes1(uint8(lenLen) + uint8(_offset) + 55);
                                for (i = 1; i <= lenLen; i++) {
                                    encoded[i] = bytes1(uint8((_len / (256**(lenLen - i))) % 256));
                                }
                            }
                            return encoded;
                        }
                        /**
                         * @notice Encode integer in big endian binary form with no leading zeroes.
                         *
                         * @param _x The integer to encode.
                         *
                         * @return RLP encoded bytes.
                         */
                        function _toBinary(uint256 _x) private pure returns (bytes memory) {
                            bytes memory b = abi.encodePacked(_x);
                            uint256 i = 0;
                            for (; i < 32; i++) {
                                if (b[i] != 0) {
                                    break;
                                }
                            }
                            bytes memory res = new bytes(32 - i);
                            for (uint256 j = 0; j < res.length; j++) {
                                res[j] = b[i++];
                            }
                            return res;
                        }
                        /**
                         * @custom:attribution https://github.com/Arachnid/solidity-stringutils
                         * @notice Copies a piece of memory to another location.
                         *
                         * @param _dest Destination location.
                         * @param _src  Source location.
                         * @param _len  Length of memory to copy.
                         */
                        function _memcpy(
                            uint256 _dest,
                            uint256 _src,
                            uint256 _len
                        ) private pure {
                            uint256 dest = _dest;
                            uint256 src = _src;
                            uint256 len = _len;
                            for (; len >= 32; len -= 32) {
                                assembly {
                                    mstore(dest, mload(src))
                                }
                                dest += 32;
                                src += 32;
                            }
                            uint256 mask;
                            unchecked {
                                mask = 256**(32 - len) - 1;
                            }
                            assembly {
                                let srcpart := and(mload(src), not(mask))
                                let destpart := and(mload(dest), mask)
                                mstore(dest, or(destpart, srcpart))
                            }
                        }
                        /**
                         * @custom:attribution https://github.com/sammayo/solidity-rlp-encoder
                         * @notice Flattens a list of byte strings into one byte string.
                         *
                         * @param _list List of byte strings to flatten.
                         *
                         * @return The flattened byte string.
                         */
                        function _flatten(bytes[] memory _list) private pure returns (bytes memory) {
                            if (_list.length == 0) {
                                return new bytes(0);
                            }
                            uint256 len;
                            uint256 i = 0;
                            for (; i < _list.length; i++) {
                                len += _list[i].length;
                            }
                            bytes memory flattened = new bytes(len);
                            uint256 flattenedPtr;
                            assembly {
                                flattenedPtr := add(flattened, 0x20)
                            }
                            for (i = 0; i < _list.length; i++) {
                                bytes memory item = _list[i];
                                uint256 listPtr;
                                assembly {
                                    listPtr := add(item, 0x20)
                                }
                                _memcpy(flattenedPtr, listPtr, item.length);
                                flattenedPtr += _list[i].length;
                            }
                            return flattened;
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    pragma solidity 0.8.15;
                    import { Initializable } from "@openzeppelin/contracts-upgradeable/proxy/utils/Initializable.sol";
                    import { SafeCall } from "../libraries/SafeCall.sol";
                    import { Hashing } from "../libraries/Hashing.sol";
                    import { Encoding } from "../libraries/Encoding.sol";
                    import { Constants } from "../libraries/Constants.sol";
                    /**
                     * @custom:legacy
                     * @title CrossDomainMessengerLegacySpacer0
                     * @notice Contract only exists to add a spacer to the CrossDomainMessenger where the
                     *         libAddressManager variable used to exist. Must be the first contract in the inheritance
                     *         tree of the CrossDomainMessenger.
                     */
                    contract CrossDomainMessengerLegacySpacer0 {
                        /**
                         * @custom:legacy
                         * @custom:spacer libAddressManager
                         * @notice Spacer for backwards compatibility.
                         */
                        address private spacer_0_0_20;
                    }
                    /**
                     * @custom:legacy
                     * @title CrossDomainMessengerLegacySpacer1
                     * @notice Contract only exists to add a spacer to the CrossDomainMessenger where the
                     *         PausableUpgradable and OwnableUpgradeable variables used to exist. Must be
                     *         the third contract in the inheritance tree of the CrossDomainMessenger.
                     */
                    contract CrossDomainMessengerLegacySpacer1 {
                        /**
                         * @custom:legacy
                         * @custom:spacer __gap
                         * @notice Spacer for backwards compatibility. Comes from OpenZeppelin
                         *         ContextUpgradable via OwnableUpgradeable.
                         *
                         */
                        uint256[50] private spacer_1_0_1600;
                        /**
                         * @custom:legacy
                         * @custom:spacer _owner
                         * @notice Spacer for backwards compatibility.
                         *         Come from OpenZeppelin OwnableUpgradeable.
                         */
                        address private spacer_51_0_20;
                        /**
                         * @custom:legacy
                         * @custom:spacer __gap
                         * @notice Spacer for backwards compatibility. Comes from OpenZeppelin
                         *         ContextUpgradable via PausableUpgradable.
                         */
                        uint256[49] private spacer_52_0_1568;
                        /**
                         * @custom:legacy
                         * @custom:spacer _paused
                         * @notice Spacer for backwards compatibility. Comes from OpenZeppelin
                         *         PausableUpgradable.
                         */
                        bool private spacer_101_0_1;
                        /**
                         * @custom:legacy
                         * @custom:spacer __gap
                         * @notice Spacer for backwards compatibility. Comes from OpenZeppelin
                         *         PausableUpgradable.
                         */
                        uint256[49] private spacer_102_0_1568;
                        /**
                         * @custom:legacy
                         * @custom:spacer ReentrancyGuardUpgradeable's `_status` field.
                         * @notice Spacer for backwards compatibility
                         */
                        uint256 private spacer_151_0_32;
                        /**
                         * @custom:spacer ReentrancyGuardUpgradeable
                         * @notice Spacer for backwards compatibility
                         */
                        uint256[49] private __gap_reentrancy_guard;
                        /**
                         * @custom:legacy
                         * @custom:spacer blockedMessages
                         * @notice Spacer for backwards compatibility.
                         */
                        mapping(bytes32 => bool) private spacer_201_0_32;
                        /**
                         * @custom:legacy
                         * @custom:spacer relayedMessages
                         * @notice Spacer for backwards compatibility.
                         */
                        mapping(bytes32 => bool) private spacer_202_0_32;
                    }
                    /**
                     * @custom:upgradeable
                     * @title CrossDomainMessenger
                     * @notice CrossDomainMessenger is a base contract that provides the core logic for the L1 and L2
                     *         cross-chain messenger contracts. It's designed to be a universal interface that only
                     *         needs to be extended slightly to provide low-level message passing functionality on each
                     *         chain it's deployed on. Currently only designed for message passing between two paired
                     *         chains and does not support one-to-many interactions.
                     *
                     *         Any changes to this contract MUST result in a semver bump for contracts that inherit it.
                     */
                    abstract contract CrossDomainMessenger is
                        CrossDomainMessengerLegacySpacer0,
                        Initializable,
                        CrossDomainMessengerLegacySpacer1
                    {
                        /**
                         * @notice Current message version identifier.
                         */
                        uint16 public constant MESSAGE_VERSION = 1;
                        /**
                         * @notice Constant overhead added to the base gas for a message.
                         */
                        uint64 public constant MIN_GAS_CONSTANT_OVERHEAD = 200_000;
                        /**
                         * @notice Numerator for dynamic overhead added to the base gas for a message.
                         */
                        uint64 public constant MIN_GAS_DYNAMIC_OVERHEAD_NUMERATOR = 1016;
                        /**
                         * @notice Denominator for dynamic overhead added to the base gas for a message.
                         */
                        uint64 public constant MIN_GAS_DYNAMIC_OVERHEAD_DENOMINATOR = 1000;
                        /**
                         * @notice Extra gas added to base gas for each byte of calldata in a message.
                         */
                        uint64 public constant MIN_GAS_CALLDATA_OVERHEAD = 16;
                        /**
                         * @notice Address of the paired CrossDomainMessenger contract on the other chain.
                         */
                        address public immutable OTHER_MESSENGER;
                        /**
                         * @notice Mapping of message hashes to boolean receipt values. Note that a message will only
                         *         be present in this mapping if it has successfully been relayed on this chain, and
                         *         can therefore not be relayed again.
                         */
                        mapping(bytes32 => bool) public successfulMessages;
                        /**
                         * @notice Address of the sender of the currently executing message on the other chain. If the
                         *         value of this variable is the default value (0x00000000...dead) then no message is
                         *         currently being executed. Use the xDomainMessageSender getter which will throw an
                         *         error if this is the case.
                         */
                        address internal xDomainMsgSender;
                        /**
                         * @notice Nonce for the next message to be sent, without the message version applied. Use the
                         *         messageNonce getter which will insert the message version into the nonce to give you
                         *         the actual nonce to be used for the message.
                         */
                        uint240 internal msgNonce;
                        /**
                         * @notice Mapping of message hashes to a boolean if and only if the message has failed to be
                         *         executed at least once. A message will not be present in this mapping if it
                         *         successfully executed on the first attempt.
                         */
                        mapping(bytes32 => bool) public failedMessages;
                        /**
                         * @notice A mapping of hashes to reentrancy locks.
                         */
                        mapping(bytes32 => bool) internal reentrancyLocks;
                        /**
                         * @notice Reserve extra slots in the storage layout for future upgrades.
                         *         A gap size of 41 was chosen here, so that the first slot used in a child contract
                         *         would be a multiple of 50.
                         */
                        uint256[41] private __gap;
                        /**
                         * @notice Emitted whenever a message is sent to the other chain.
                         *
                         * @param target       Address of the recipient of the message.
                         * @param sender       Address of the sender of the message.
                         * @param message      Message to trigger the recipient address with.
                         * @param messageNonce Unique nonce attached to the message.
                         * @param gasLimit     Minimum gas limit that the message can be executed with.
                         */
                        event SentMessage(
                            address indexed target,
                            address sender,
                            bytes message,
                            uint256 messageNonce,
                            uint256 gasLimit
                        );
                        /**
                         * @notice Additional event data to emit, required as of Bedrock. Cannot be merged with the
                         *         SentMessage event without breaking the ABI of this contract, this is good enough.
                         *
                         * @param sender Address of the sender of the message.
                         * @param value  ETH value sent along with the message to the recipient.
                         */
                        event SentMessageExtension1(address indexed sender, uint256 value);
                        /**
                         * @notice Emitted whenever a message is successfully relayed on this chain.
                         *
                         * @param msgHash Hash of the message that was relayed.
                         */
                        event RelayedMessage(bytes32 indexed msgHash);
                        /**
                         * @notice Emitted whenever a message fails to be relayed on this chain.
                         *
                         * @param msgHash Hash of the message that failed to be relayed.
                         */
                        event FailedRelayedMessage(bytes32 indexed msgHash);
                        /**
                         * @param _otherMessenger Address of the messenger on the paired chain.
                         */
                        constructor(address _otherMessenger) {
                            OTHER_MESSENGER = _otherMessenger;
                        }
                        /**
                         * @notice Sends a message to some target address on the other chain. Note that if the call
                         *         always reverts, then the message will be unrelayable, and any ETH sent will be
                         *         permanently locked. The same will occur if the target on the other chain is
                         *         considered unsafe (see the _isUnsafeTarget() function).
                         *
                         * @param _target      Target contract or wallet address.
                         * @param _message     Message to trigger the target address with.
                         * @param _minGasLimit Minimum gas limit that the message can be executed with.
                         */
                        function sendMessage(
                            address _target,
                            bytes calldata _message,
                            uint32 _minGasLimit
                        ) external payable {
                            // Triggers a message to the other messenger. Note that the amount of gas provided to the
                            // message is the amount of gas requested by the user PLUS the base gas value. We want to
                            // guarantee the property that the call to the target contract will always have at least
                            // the minimum gas limit specified by the user.
                            _sendMessage(
                                OTHER_MESSENGER,
                                baseGas(_message, _minGasLimit),
                                msg.value,
                                abi.encodeWithSelector(
                                    this.relayMessage.selector,
                                    messageNonce(),
                                    msg.sender,
                                    _target,
                                    msg.value,
                                    _minGasLimit,
                                    _message
                                )
                            );
                            emit SentMessage(_target, msg.sender, _message, messageNonce(), _minGasLimit);
                            emit SentMessageExtension1(msg.sender, msg.value);
                            unchecked {
                                ++msgNonce;
                            }
                        }
                        /**
                         * @notice Relays a message that was sent by the other CrossDomainMessenger contract. Can only
                         *         be executed via cross-chain call from the other messenger OR if the message was
                         *         already received once and is currently being replayed.
                         *
                         * @param _nonce       Nonce of the message being relayed.
                         * @param _sender      Address of the user who sent the message.
                         * @param _target      Address that the message is targeted at.
                         * @param _value       ETH value to send with the message.
                         * @param _minGasLimit Minimum amount of gas that the message can be executed with.
                         * @param _message     Message to send to the target.
                         */
                        function relayMessage(
                            uint256 _nonce,
                            address _sender,
                            address _target,
                            uint256 _value,
                            uint256 _minGasLimit,
                            bytes calldata _message
                        ) external payable {
                            (, uint16 version) = Encoding.decodeVersionedNonce(_nonce);
                            require(
                                version < 2,
                                "CrossDomainMessenger: only version 0 or 1 messages are supported at this time"
                            );
                            // If the message is version 0, then it's a migrated legacy withdrawal. We therefore need
                            // to check that the legacy version of the message has not already been relayed.
                            if (version == 0) {
                                bytes32 oldHash = Hashing.hashCrossDomainMessageV0(_target, _sender, _message, _nonce);
                                require(
                                    successfulMessages[oldHash] == false,
                                    "CrossDomainMessenger: legacy withdrawal already relayed"
                                );
                            }
                            // We use the v1 message hash as the unique identifier for the message because it commits
                            // to the value and minimum gas limit of the message.
                            bytes32 versionedHash = Hashing.hashCrossDomainMessageV1(
                                _nonce,
                                _sender,
                                _target,
                                _value,
                                _minGasLimit,
                                _message
                            );
                            // Check if the reentrancy lock for the `versionedHash` is already set.
                            if (reentrancyLocks[versionedHash]) {
                                revert("ReentrancyGuard: reentrant call");
                            }
                            // Trigger the reentrancy lock for `versionedHash`
                            reentrancyLocks[versionedHash] = true;
                            if (_isOtherMessenger()) {
                                // These properties should always hold when the message is first submitted (as
                                // opposed to being replayed).
                                assert(msg.value == _value);
                                assert(!failedMessages[versionedHash]);
                            } else {
                                require(
                                    msg.value == 0,
                                    "CrossDomainMessenger: value must be zero unless message is from a system address"
                                );
                                require(
                                    failedMessages[versionedHash],
                                    "CrossDomainMessenger: message cannot be replayed"
                                );
                            }
                            require(
                                _isUnsafeTarget(_target) == false,
                                "CrossDomainMessenger: cannot send message to blocked system address"
                            );
                            require(
                                successfulMessages[versionedHash] == false,
                                "CrossDomainMessenger: message has already been relayed"
                            );
                            xDomainMsgSender = _sender;
                            bool success = SafeCall.callWithMinGas(_target, _minGasLimit, _value, _message);
                            xDomainMsgSender = Constants.DEFAULT_L2_SENDER;
                            if (success) {
                                successfulMessages[versionedHash] = true;
                                emit RelayedMessage(versionedHash);
                            } else {
                                failedMessages[versionedHash] = true;
                                emit FailedRelayedMessage(versionedHash);
                                // Revert in this case if the transaction was triggered by the estimation address. This
                                // should only be possible during gas estimation or we have bigger problems. Reverting
                                // here will make the behavior of gas estimation change such that the gas limit
                                // computed will be the amount required to relay the message, even if that amount is
                                // greater than the minimum gas limit specified by the user.
                                if (tx.origin == Constants.ESTIMATION_ADDRESS) {
                                    revert("CrossDomainMessenger: failed to relay message");
                                }
                            }
                            // Clear the reentrancy lock for `versionedHash`
                            reentrancyLocks[versionedHash] = false;
                        }
                        /**
                         * @notice Retrieves the address of the contract or wallet that initiated the currently
                         *         executing message on the other chain. Will throw an error if there is no message
                         *         currently being executed. Allows the recipient of a call to see who triggered it.
                         *
                         * @return Address of the sender of the currently executing message on the other chain.
                         */
                        function xDomainMessageSender() external view returns (address) {
                            require(
                                xDomainMsgSender != Constants.DEFAULT_L2_SENDER,
                                "CrossDomainMessenger: xDomainMessageSender is not set"
                            );
                            return xDomainMsgSender;
                        }
                        /**
                         * @notice Retrieves the next message nonce. Message version will be added to the upper two
                         *         bytes of the message nonce. Message version allows us to treat messages as having
                         *         different structures.
                         *
                         * @return Nonce of the next message to be sent, with added message version.
                         */
                        function messageNonce() public view returns (uint256) {
                            return Encoding.encodeVersionedNonce(msgNonce, MESSAGE_VERSION);
                        }
                        /**
                         * @notice Computes the amount of gas required to guarantee that a given message will be
                         *         received on the other chain without running out of gas. Guaranteeing that a message
                         *         will not run out of gas is important because this ensures that a message can always
                         *         be replayed on the other chain if it fails to execute completely.
                         *
                         * @param _message     Message to compute the amount of required gas for.
                         * @param _minGasLimit Minimum desired gas limit when message goes to target.
                         *
                         * @return Amount of gas required to guarantee message receipt.
                         */
                        function baseGas(bytes calldata _message, uint32 _minGasLimit) public pure returns (uint64) {
                            // We peform the following math on uint64s to avoid overflow errors. Multiplying the
                            // by MIN_GAS_DYNAMIC_OVERHEAD_NUMERATOR would otherwise limit the _minGasLimit to
                            // type(uint32).max / MIN_GAS_DYNAMIC_OVERHEAD_NUMERATOR ~= 4.2m.
                            return
                                // Dynamic overhead
                                ((uint64(_minGasLimit) * MIN_GAS_DYNAMIC_OVERHEAD_NUMERATOR) /
                                    MIN_GAS_DYNAMIC_OVERHEAD_DENOMINATOR) +
                                // Calldata overhead
                                (uint64(_message.length) * MIN_GAS_CALLDATA_OVERHEAD) +
                                // Constant overhead
                                MIN_GAS_CONSTANT_OVERHEAD;
                        }
                        /**
                         * @notice Intializer.
                         */
                        // solhint-disable-next-line func-name-mixedcase
                        function __CrossDomainMessenger_init() internal onlyInitializing {
                            xDomainMsgSender = Constants.DEFAULT_L2_SENDER;
                        }
                        /**
                         * @notice Sends a low-level message to the other messenger. Needs to be implemented by child
                         *         contracts because the logic for this depends on the network where the messenger is
                         *         being deployed.
                         *
                         * @param _to       Recipient of the message on the other chain.
                         * @param _gasLimit Minimum gas limit the message can be executed with.
                         * @param _value    Amount of ETH to send with the message.
                         * @param _data     Message data.
                         */
                        function _sendMessage(
                            address _to,
                            uint64 _gasLimit,
                            uint256 _value,
                            bytes memory _data
                        ) internal virtual;
                        /**
                         * @notice Checks whether the message is coming from the other messenger. Implemented by child
                         *         contracts because the logic for this depends on the network where the messenger is
                         *         being deployed.
                         *
                         * @return Whether the message is coming from the other messenger.
                         */
                        function _isOtherMessenger() internal view virtual returns (bool);
                        /**
                         * @notice Checks whether a given call target is a system address that could cause the
                         *         messenger to peform an unsafe action. This is NOT a mechanism for blocking user
                         *         addresses. This is ONLY used to prevent the execution of messages to specific
                         *         system addresses that could cause security issues, e.g., having the
                         *         CrossDomainMessenger send messages to itself.
                         *
                         * @param _target Address of the contract to check.
                         *
                         * @return Whether or not the address is an unsafe system address.
                         */
                        function _isUnsafeTarget(address _target) internal view virtual returns (bool);
                    }
                    // SPDX-License-Identifier: MIT
                    pragma solidity ^0.8.0;
                    import { IERC165 } from "@openzeppelin/contracts/utils/introspection/IERC165.sol";
                    /**
                     * @title IOptimismMintableERC20
                     * @notice This interface is available on the OptimismMintableERC20 contract. We declare it as a
                     *         separate interface so that it can be used in custom implementations of
                     *         OptimismMintableERC20.
                     */
                    interface IOptimismMintableERC20 is IERC165 {
                        function remoteToken() external view returns (address);
                        function bridge() external returns (address);
                        function mint(address _to, uint256 _amount) external;
                        function burn(address _from, uint256 _amount) external;
                    }
                    /**
                     * @custom:legacy
                     * @title ILegacyMintableERC20
                     * @notice This interface was available on the legacy L2StandardERC20 contract. It remains available
                     *         on the OptimismMintableERC20 contract for backwards compatibility.
                     */
                    interface ILegacyMintableERC20 is IERC165 {
                        function l1Token() external view returns (address);
                        function mint(address _to, uint256 _amount) external;
                        function burn(address _from, uint256 _amount) external;
                    }
                    // SPDX-License-Identifier: MIT
                    pragma solidity 0.8.15;
                    import { ERC20 } from "@openzeppelin/contracts/token/ERC20/ERC20.sol";
                    import { IERC165 } from "@openzeppelin/contracts/utils/introspection/IERC165.sol";
                    import { ILegacyMintableERC20, IOptimismMintableERC20 } from "./IOptimismMintableERC20.sol";
                    import { Semver } from "../universal/Semver.sol";
                    /**
                     * @title OptimismMintableERC20
                     * @notice OptimismMintableERC20 is a standard extension of the base ERC20 token contract designed
                     *         to allow the StandardBridge contracts to mint and burn tokens. This makes it possible to
                     *         use an OptimismMintablERC20 as the L2 representation of an L1 token, or vice-versa.
                     *         Designed to be backwards compatible with the older StandardL2ERC20 token which was only
                     *         meant for use on L2.
                     */
                    contract OptimismMintableERC20 is IOptimismMintableERC20, ILegacyMintableERC20, ERC20, Semver {
                        /**
                         * @notice Address of the corresponding version of this token on the remote chain.
                         */
                        address public immutable REMOTE_TOKEN;
                        /**
                         * @notice Address of the StandardBridge on this network.
                         */
                        address public immutable BRIDGE;
                        /**
                         * @notice Emitted whenever tokens are minted for an account.
                         *
                         * @param account Address of the account tokens are being minted for.
                         * @param amount  Amount of tokens minted.
                         */
                        event Mint(address indexed account, uint256 amount);
                        /**
                         * @notice Emitted whenever tokens are burned from an account.
                         *
                         * @param account Address of the account tokens are being burned from.
                         * @param amount  Amount of tokens burned.
                         */
                        event Burn(address indexed account, uint256 amount);
                        /**
                         * @notice A modifier that only allows the bridge to call
                         */
                        modifier onlyBridge() {
                            require(msg.sender == BRIDGE, "OptimismMintableERC20: only bridge can mint and burn");
                            _;
                        }
                        /**
                         * @custom:semver 1.0.0
                         *
                         * @param _bridge      Address of the L2 standard bridge.
                         * @param _remoteToken Address of the corresponding L1 token.
                         * @param _name        ERC20 name.
                         * @param _symbol      ERC20 symbol.
                         */
                        constructor(
                            address _bridge,
                            address _remoteToken,
                            string memory _name,
                            string memory _symbol
                        ) ERC20(_name, _symbol) Semver(1, 0, 0) {
                            REMOTE_TOKEN = _remoteToken;
                            BRIDGE = _bridge;
                        }
                        /**
                         * @notice Allows the StandardBridge on this network to mint tokens.
                         *
                         * @param _to     Address to mint tokens to.
                         * @param _amount Amount of tokens to mint.
                         */
                        function mint(address _to, uint256 _amount)
                            external
                            virtual
                            override(IOptimismMintableERC20, ILegacyMintableERC20)
                            onlyBridge
                        {
                            _mint(_to, _amount);
                            emit Mint(_to, _amount);
                        }
                        /**
                         * @notice Allows the StandardBridge on this network to burn tokens.
                         *
                         * @param _from   Address to burn tokens from.
                         * @param _amount Amount of tokens to burn.
                         */
                        function burn(address _from, uint256 _amount)
                            external
                            virtual
                            override(IOptimismMintableERC20, ILegacyMintableERC20)
                            onlyBridge
                        {
                            _burn(_from, _amount);
                            emit Burn(_from, _amount);
                        }
                        /**
                         * @notice ERC165 interface check function.
                         *
                         * @param _interfaceId Interface ID to check.
                         *
                         * @return Whether or not the interface is supported by this contract.
                         */
                        function supportsInterface(bytes4 _interfaceId) external pure returns (bool) {
                            bytes4 iface1 = type(IERC165).interfaceId;
                            // Interface corresponding to the legacy L2StandardERC20.
                            bytes4 iface2 = type(ILegacyMintableERC20).interfaceId;
                            // Interface corresponding to the updated OptimismMintableERC20 (this contract).
                            bytes4 iface3 = type(IOptimismMintableERC20).interfaceId;
                            return _interfaceId == iface1 || _interfaceId == iface2 || _interfaceId == iface3;
                        }
                        /**
                         * @custom:legacy
                         * @notice Legacy getter for the remote token. Use REMOTE_TOKEN going forward.
                         */
                        function l1Token() public view returns (address) {
                            return REMOTE_TOKEN;
                        }
                        /**
                         * @custom:legacy
                         * @notice Legacy getter for the bridge. Use BRIDGE going forward.
                         */
                        function l2Bridge() public view returns (address) {
                            return BRIDGE;
                        }
                        /**
                         * @custom:legacy
                         * @notice Legacy getter for REMOTE_TOKEN.
                         */
                        function remoteToken() public view returns (address) {
                            return REMOTE_TOKEN;
                        }
                        /**
                         * @custom:legacy
                         * @notice Legacy getter for BRIDGE.
                         */
                        function bridge() public view returns (address) {
                            return BRIDGE;
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    pragma solidity ^0.8.0;
                    import { Strings } from "@openzeppelin/contracts/utils/Strings.sol";
                    /**
                     * @title Semver
                     * @notice Semver is a simple contract for managing contract versions.
                     */
                    contract Semver {
                        /**
                         * @notice Contract version number (major).
                         */
                        uint256 private immutable MAJOR_VERSION;
                        /**
                         * @notice Contract version number (minor).
                         */
                        uint256 private immutable MINOR_VERSION;
                        /**
                         * @notice Contract version number (patch).
                         */
                        uint256 private immutable PATCH_VERSION;
                        /**
                         * @param _major Version number (major).
                         * @param _minor Version number (minor).
                         * @param _patch Version number (patch).
                         */
                        constructor(
                            uint256 _major,
                            uint256 _minor,
                            uint256 _patch
                        ) {
                            MAJOR_VERSION = _major;
                            MINOR_VERSION = _minor;
                            PATCH_VERSION = _patch;
                        }
                        /**
                         * @notice Returns the full semver contract version.
                         *
                         * @return Semver contract version as a string.
                         */
                        function version() public view returns (string memory) {
                            return
                                string(
                                    abi.encodePacked(
                                        Strings.toString(MAJOR_VERSION),
                                        ".",
                                        Strings.toString(MINOR_VERSION),
                                        ".",
                                        Strings.toString(PATCH_VERSION)
                                    )
                                );
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    pragma solidity 0.8.15;
                    import { IERC20 } from "@openzeppelin/contracts/token/ERC20/IERC20.sol";
                    import { ERC165Checker } from "@openzeppelin/contracts/utils/introspection/ERC165Checker.sol";
                    import { Address } from "@openzeppelin/contracts/utils/Address.sol";
                    import { SafeERC20 } from "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
                    import { SafeCall } from "../libraries/SafeCall.sol";
                    import { IOptimismMintableERC20, ILegacyMintableERC20 } from "./IOptimismMintableERC20.sol";
                    import { CrossDomainMessenger } from "./CrossDomainMessenger.sol";
                    import { OptimismMintableERC20 } from "./OptimismMintableERC20.sol";
                    /**
                     * @custom:upgradeable
                     * @title StandardBridge
                     * @notice StandardBridge is a base contract for the L1 and L2 standard ERC20 bridges. It handles
                     *         the core bridging logic, including escrowing tokens that are native to the local chain
                     *         and minting/burning tokens that are native to the remote chain.
                     */
                    abstract contract StandardBridge {
                        using SafeERC20 for IERC20;
                        /**
                         * @notice The L2 gas limit set when eth is depoisited using the receive() function.
                         */
                        uint32 internal constant RECEIVE_DEFAULT_GAS_LIMIT = 200_000;
                        /**
                         * @notice Messenger contract on this domain.
                         */
                        CrossDomainMessenger public immutable MESSENGER;
                        /**
                         * @notice Corresponding bridge on the other domain.
                         */
                        StandardBridge public immutable OTHER_BRIDGE;
                        /**
                         * @custom:legacy
                         * @custom:spacer messenger
                         * @notice Spacer for backwards compatibility.
                         */
                        address private spacer_0_0_20;
                        /**
                         * @custom:legacy
                         * @custom:spacer l2TokenBridge
                         * @notice Spacer for backwards compatibility.
                         */
                        address private spacer_1_0_20;
                        /**
                         * @notice Mapping that stores deposits for a given pair of local and remote tokens.
                         */
                        mapping(address => mapping(address => uint256)) public deposits;
                        /**
                         * @notice Reserve extra slots (to a total of 50) in the storage layout for future upgrades.
                         *         A gap size of 47 was chosen here, so that the first slot used in a child contract
                         *         would be a multiple of 50.
                         */
                        uint256[47] private __gap;
                        /**
                         * @notice Emitted when an ETH bridge is initiated to the other chain.
                         *
                         * @param from      Address of the sender.
                         * @param to        Address of the receiver.
                         * @param amount    Amount of ETH sent.
                         * @param extraData Extra data sent with the transaction.
                         */
                        event ETHBridgeInitiated(
                            address indexed from,
                            address indexed to,
                            uint256 amount,
                            bytes extraData
                        );
                        /**
                         * @notice Emitted when an ETH bridge is finalized on this chain.
                         *
                         * @param from      Address of the sender.
                         * @param to        Address of the receiver.
                         * @param amount    Amount of ETH sent.
                         * @param extraData Extra data sent with the transaction.
                         */
                        event ETHBridgeFinalized(
                            address indexed from,
                            address indexed to,
                            uint256 amount,
                            bytes extraData
                        );
                        /**
                         * @notice Emitted when an ERC20 bridge is initiated to the other chain.
                         *
                         * @param localToken  Address of the ERC20 on this chain.
                         * @param remoteToken Address of the ERC20 on the remote chain.
                         * @param from        Address of the sender.
                         * @param to          Address of the receiver.
                         * @param amount      Amount of the ERC20 sent.
                         * @param extraData   Extra data sent with the transaction.
                         */
                        event ERC20BridgeInitiated(
                            address indexed localToken,
                            address indexed remoteToken,
                            address indexed from,
                            address to,
                            uint256 amount,
                            bytes extraData
                        );
                        /**
                         * @notice Emitted when an ERC20 bridge is finalized on this chain.
                         *
                         * @param localToken  Address of the ERC20 on this chain.
                         * @param remoteToken Address of the ERC20 on the remote chain.
                         * @param from        Address of the sender.
                         * @param to          Address of the receiver.
                         * @param amount      Amount of the ERC20 sent.
                         * @param extraData   Extra data sent with the transaction.
                         */
                        event ERC20BridgeFinalized(
                            address indexed localToken,
                            address indexed remoteToken,
                            address indexed from,
                            address to,
                            uint256 amount,
                            bytes extraData
                        );
                        /**
                         * @notice Only allow EOAs to call the functions. Note that this is not safe against contracts
                         *         calling code within their constructors, but also doesn't really matter since we're
                         *         just trying to prevent users accidentally depositing with smart contract wallets.
                         */
                        modifier onlyEOA() {
                            require(
                                !Address.isContract(msg.sender),
                                "StandardBridge: function can only be called from an EOA"
                            );
                            _;
                        }
                        /**
                         * @notice Ensures that the caller is a cross-chain message from the other bridge.
                         */
                        modifier onlyOtherBridge() {
                            require(
                                msg.sender == address(MESSENGER) &&
                                    MESSENGER.xDomainMessageSender() == address(OTHER_BRIDGE),
                                "StandardBridge: function can only be called from the other bridge"
                            );
                            _;
                        }
                        /**
                         * @param _messenger   Address of CrossDomainMessenger on this network.
                         * @param _otherBridge Address of the other StandardBridge contract.
                         */
                        constructor(address payable _messenger, address payable _otherBridge) {
                            MESSENGER = CrossDomainMessenger(_messenger);
                            OTHER_BRIDGE = StandardBridge(_otherBridge);
                        }
                        /**
                         * @notice Allows EOAs to bridge ETH by sending directly to the bridge.
                         *         Must be implemented by contracts that inherit.
                         */
                        receive() external payable virtual;
                        /**
                         * @custom:legacy
                         * @notice Legacy getter for messenger contract.
                         *
                         * @return Messenger contract on this domain.
                         */
                        function messenger() external view returns (CrossDomainMessenger) {
                            return MESSENGER;
                        }
                        /**
                         * @notice Sends ETH to the sender's address on the other chain.
                         *
                         * @param _minGasLimit Minimum amount of gas that the bridge can be relayed with.
                         * @param _extraData   Extra data to be sent with the transaction. Note that the recipient will
                         *                     not be triggered with this data, but it will be emitted and can be used
                         *                     to identify the transaction.
                         */
                        function bridgeETH(uint32 _minGasLimit, bytes calldata _extraData) public payable onlyEOA {
                            _initiateBridgeETH(msg.sender, msg.sender, msg.value, _minGasLimit, _extraData);
                        }
                        /**
                         * @notice Sends ETH to a receiver's address on the other chain. Note that if ETH is sent to a
                         *         smart contract and the call fails, the ETH will be temporarily locked in the
                         *         StandardBridge on the other chain until the call is replayed. If the call cannot be
                         *         replayed with any amount of gas (call always reverts), then the ETH will be
                         *         permanently locked in the StandardBridge on the other chain. ETH will also
                         *         be locked if the receiver is the other bridge, because finalizeBridgeETH will revert
                         *         in that case.
                         *
                         * @param _to          Address of the receiver.
                         * @param _minGasLimit Minimum amount of gas that the bridge can be relayed with.
                         * @param _extraData   Extra data to be sent with the transaction. Note that the recipient will
                         *                     not be triggered with this data, but it will be emitted and can be used
                         *                     to identify the transaction.
                         */
                        function bridgeETHTo(
                            address _to,
                            uint32 _minGasLimit,
                            bytes calldata _extraData
                        ) public payable {
                            _initiateBridgeETH(msg.sender, _to, msg.value, _minGasLimit, _extraData);
                        }
                        /**
                         * @notice Sends ERC20 tokens to the sender's address on the other chain. Note that if the
                         *         ERC20 token on the other chain does not recognize the local token as the correct
                         *         pair token, the ERC20 bridge will fail and the tokens will be returned to sender on
                         *         this chain.
                         *
                         * @param _localToken  Address of the ERC20 on this chain.
                         * @param _remoteToken Address of the corresponding token on the remote chain.
                         * @param _amount      Amount of local tokens to deposit.
                         * @param _minGasLimit Minimum amount of gas that the bridge can be relayed with.
                         * @param _extraData   Extra data to be sent with the transaction. Note that the recipient will
                         *                     not be triggered with this data, but it will be emitted and can be used
                         *                     to identify the transaction.
                         */
                        function bridgeERC20(
                            address _localToken,
                            address _remoteToken,
                            uint256 _amount,
                            uint32 _minGasLimit,
                            bytes calldata _extraData
                        ) public virtual onlyEOA {
                            _initiateBridgeERC20(
                                _localToken,
                                _remoteToken,
                                msg.sender,
                                msg.sender,
                                _amount,
                                _minGasLimit,
                                _extraData
                            );
                        }
                        /**
                         * @notice Sends ERC20 tokens to a receiver's address on the other chain. Note that if the
                         *         ERC20 token on the other chain does not recognize the local token as the correct
                         *         pair token, the ERC20 bridge will fail and the tokens will be returned to sender on
                         *         this chain.
                         *
                         * @param _localToken  Address of the ERC20 on this chain.
                         * @param _remoteToken Address of the corresponding token on the remote chain.
                         * @param _to          Address of the receiver.
                         * @param _amount      Amount of local tokens to deposit.
                         * @param _minGasLimit Minimum amount of gas that the bridge can be relayed with.
                         * @param _extraData   Extra data to be sent with the transaction. Note that the recipient will
                         *                     not be triggered with this data, but it will be emitted and can be used
                         *                     to identify the transaction.
                         */
                        function bridgeERC20To(
                            address _localToken,
                            address _remoteToken,
                            address _to,
                            uint256 _amount,
                            uint32 _minGasLimit,
                            bytes calldata _extraData
                        ) public virtual {
                            _initiateBridgeERC20(
                                _localToken,
                                _remoteToken,
                                msg.sender,
                                _to,
                                _amount,
                                _minGasLimit,
                                _extraData
                            );
                        }
                        /**
                         * @notice Finalizes an ETH bridge on this chain. Can only be triggered by the other
                         *         StandardBridge contract on the remote chain.
                         *
                         * @param _from      Address of the sender.
                         * @param _to        Address of the receiver.
                         * @param _amount    Amount of ETH being bridged.
                         * @param _extraData Extra data to be sent with the transaction. Note that the recipient will
                         *                   not be triggered with this data, but it will be emitted and can be used
                         *                   to identify the transaction.
                         */
                        function finalizeBridgeETH(
                            address _from,
                            address _to,
                            uint256 _amount,
                            bytes calldata _extraData
                        ) public payable onlyOtherBridge {
                            require(msg.value == _amount, "StandardBridge: amount sent does not match amount required");
                            require(_to != address(this), "StandardBridge: cannot send to self");
                            require(_to != address(MESSENGER), "StandardBridge: cannot send to messenger");
                            // Emit the correct events. By default this will be _amount, but child
                            // contracts may override this function in order to emit legacy events as well.
                            _emitETHBridgeFinalized(_from, _to, _amount, _extraData);
                            bool success = SafeCall.call(_to, gasleft(), _amount, hex"");
                            require(success, "StandardBridge: ETH transfer failed");
                        }
                        /**
                         * @notice Finalizes an ERC20 bridge on this chain. Can only be triggered by the other
                         *         StandardBridge contract on the remote chain.
                         *
                         * @param _localToken  Address of the ERC20 on this chain.
                         * @param _remoteToken Address of the corresponding token on the remote chain.
                         * @param _from        Address of the sender.
                         * @param _to          Address of the receiver.
                         * @param _amount      Amount of the ERC20 being bridged.
                         * @param _extraData   Extra data to be sent with the transaction. Note that the recipient will
                         *                     not be triggered with this data, but it will be emitted and can be used
                         *                     to identify the transaction.
                         */
                        function finalizeBridgeERC20(
                            address _localToken,
                            address _remoteToken,
                            address _from,
                            address _to,
                            uint256 _amount,
                            bytes calldata _extraData
                        ) public onlyOtherBridge {
                            if (_isOptimismMintableERC20(_localToken)) {
                                require(
                                    _isCorrectTokenPair(_localToken, _remoteToken),
                                    "StandardBridge: wrong remote token for Optimism Mintable ERC20 local token"
                                );
                                OptimismMintableERC20(_localToken).mint(_to, _amount);
                            } else {
                                deposits[_localToken][_remoteToken] = deposits[_localToken][_remoteToken] - _amount;
                                IERC20(_localToken).safeTransfer(_to, _amount);
                            }
                            // Emit the correct events. By default this will be ERC20BridgeFinalized, but child
                            // contracts may override this function in order to emit legacy events as well.
                            _emitERC20BridgeFinalized(_localToken, _remoteToken, _from, _to, _amount, _extraData);
                        }
                        /**
                         * @notice Initiates a bridge of ETH through the CrossDomainMessenger.
                         *
                         * @param _from        Address of the sender.
                         * @param _to          Address of the receiver.
                         * @param _amount      Amount of ETH being bridged.
                         * @param _minGasLimit Minimum amount of gas that the bridge can be relayed with.
                         * @param _extraData   Extra data to be sent with the transaction. Note that the recipient will
                         *                     not be triggered with this data, but it will be emitted and can be used
                         *                     to identify the transaction.
                         */
                        function _initiateBridgeETH(
                            address _from,
                            address _to,
                            uint256 _amount,
                            uint32 _minGasLimit,
                            bytes memory _extraData
                        ) internal {
                            require(
                                msg.value == _amount,
                                "StandardBridge: bridging ETH must include sufficient ETH value"
                            );
                            // Emit the correct events. By default this will be _amount, but child
                            // contracts may override this function in order to emit legacy events as well.
                            _emitETHBridgeInitiated(_from, _to, _amount, _extraData);
                            MESSENGER.sendMessage{ value: _amount }(
                                address(OTHER_BRIDGE),
                                abi.encodeWithSelector(
                                    this.finalizeBridgeETH.selector,
                                    _from,
                                    _to,
                                    _amount,
                                    _extraData
                                ),
                                _minGasLimit
                            );
                        }
                        /**
                         * @notice Sends ERC20 tokens to a receiver's address on the other chain.
                         *
                         * @param _localToken  Address of the ERC20 on this chain.
                         * @param _remoteToken Address of the corresponding token on the remote chain.
                         * @param _to          Address of the receiver.
                         * @param _amount      Amount of local tokens to deposit.
                         * @param _minGasLimit Minimum amount of gas that the bridge can be relayed with.
                         * @param _extraData   Extra data to be sent with the transaction. Note that the recipient will
                         *                     not be triggered with this data, but it will be emitted and can be used
                         *                     to identify the transaction.
                         */
                        function _initiateBridgeERC20(
                            address _localToken,
                            address _remoteToken,
                            address _from,
                            address _to,
                            uint256 _amount,
                            uint32 _minGasLimit,
                            bytes memory _extraData
                        ) internal {
                            if (_isOptimismMintableERC20(_localToken)) {
                                require(
                                    _isCorrectTokenPair(_localToken, _remoteToken),
                                    "StandardBridge: wrong remote token for Optimism Mintable ERC20 local token"
                                );
                                OptimismMintableERC20(_localToken).burn(_from, _amount);
                            } else {
                                IERC20(_localToken).safeTransferFrom(_from, address(this), _amount);
                                deposits[_localToken][_remoteToken] = deposits[_localToken][_remoteToken] + _amount;
                            }
                            // Emit the correct events. By default this will be ERC20BridgeInitiated, but child
                            // contracts may override this function in order to emit legacy events as well.
                            _emitERC20BridgeInitiated(_localToken, _remoteToken, _from, _to, _amount, _extraData);
                            MESSENGER.sendMessage(
                                address(OTHER_BRIDGE),
                                abi.encodeWithSelector(
                                    this.finalizeBridgeERC20.selector,
                                    // Because this call will be executed on the remote chain, we reverse the order of
                                    // the remote and local token addresses relative to their order in the
                                    // finalizeBridgeERC20 function.
                                    _remoteToken,
                                    _localToken,
                                    _from,
                                    _to,
                                    _amount,
                                    _extraData
                                ),
                                _minGasLimit
                            );
                        }
                        /**
                         * @notice Checks if a given address is an OptimismMintableERC20. Not perfect, but good enough.
                         *         Just the way we like it.
                         *
                         * @param _token Address of the token to check.
                         *
                         * @return True if the token is an OptimismMintableERC20.
                         */
                        function _isOptimismMintableERC20(address _token) internal view returns (bool) {
                            return
                                ERC165Checker.supportsInterface(_token, type(ILegacyMintableERC20).interfaceId) ||
                                ERC165Checker.supportsInterface(_token, type(IOptimismMintableERC20).interfaceId);
                        }
                        /**
                         * @notice Checks if the "other token" is the correct pair token for the OptimismMintableERC20.
                         *         Calls can be saved in the future by combining this logic with
                         *         `_isOptimismMintableERC20`.
                         *
                         * @param _mintableToken OptimismMintableERC20 to check against.
                         * @param _otherToken    Pair token to check.
                         *
                         * @return True if the other token is the correct pair token for the OptimismMintableERC20.
                         */
                        function _isCorrectTokenPair(address _mintableToken, address _otherToken)
                            internal
                            view
                            returns (bool)
                        {
                            if (
                                ERC165Checker.supportsInterface(_mintableToken, type(ILegacyMintableERC20).interfaceId)
                            ) {
                                return _otherToken == ILegacyMintableERC20(_mintableToken).l1Token();
                            } else {
                                return _otherToken == IOptimismMintableERC20(_mintableToken).remoteToken();
                            }
                        }
                        /** @notice Emits the ETHBridgeInitiated event and if necessary the appropriate legacy event
                         *          when an ETH bridge is finalized on this chain.
                         *
                         * @param _from      Address of the sender.
                         * @param _to        Address of the receiver.
                         * @param _amount    Amount of ETH sent.
                         * @param _extraData Extra data sent with the transaction.
                         */
                        function _emitETHBridgeInitiated(
                            address _from,
                            address _to,
                            uint256 _amount,
                            bytes memory _extraData
                        ) internal virtual {
                            emit ETHBridgeInitiated(_from, _to, _amount, _extraData);
                        }
                        /**
                         * @notice Emits the ETHBridgeFinalized and if necessary the appropriate legacy event when an
                         *         ETH bridge is finalized on this chain.
                         *
                         * @param _from      Address of the sender.
                         * @param _to        Address of the receiver.
                         * @param _amount    Amount of ETH sent.
                         * @param _extraData Extra data sent with the transaction.
                         */
                        function _emitETHBridgeFinalized(
                            address _from,
                            address _to,
                            uint256 _amount,
                            bytes memory _extraData
                        ) internal virtual {
                            emit ETHBridgeFinalized(_from, _to, _amount, _extraData);
                        }
                        /**
                         * @notice Emits the ERC20BridgeInitiated event and if necessary the appropriate legacy
                         *         event when an ERC20 bridge is initiated to the other chain.
                         *
                         * @param _localToken  Address of the ERC20 on this chain.
                         * @param _remoteToken Address of the ERC20 on the remote chain.
                         * @param _from        Address of the sender.
                         * @param _to          Address of the receiver.
                         * @param _amount      Amount of the ERC20 sent.
                         * @param _extraData   Extra data sent with the transaction.
                         */
                        function _emitERC20BridgeInitiated(
                            address _localToken,
                            address _remoteToken,
                            address _from,
                            address _to,
                            uint256 _amount,
                            bytes memory _extraData
                        ) internal virtual {
                            emit ERC20BridgeInitiated(_localToken, _remoteToken, _from, _to, _amount, _extraData);
                        }
                        /**
                         * @notice Emits the ERC20BridgeFinalized event and if necessary the appropriate legacy
                         *         event when an ERC20 bridge is initiated to the other chain.
                         *
                         * @param _localToken  Address of the ERC20 on this chain.
                         * @param _remoteToken Address of the ERC20 on the remote chain.
                         * @param _from        Address of the sender.
                         * @param _to          Address of the receiver.
                         * @param _amount      Amount of the ERC20 sent.
                         * @param _extraData   Extra data sent with the transaction.
                         */
                        function _emitERC20BridgeFinalized(
                            address _localToken,
                            address _remoteToken,
                            address _from,
                            address _to,
                            uint256 _amount,
                            bytes memory _extraData
                        ) internal virtual {
                            emit ERC20BridgeFinalized(_localToken, _remoteToken, _from, _to, _amount, _extraData);
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    // OpenZeppelin Contracts (last updated v4.7.0) (proxy/utils/Initializable.sol)
                    pragma solidity ^0.8.2;
                    import "../../utils/Address.sol";
                    /**
                     * @dev This is a base contract to aid in writing upgradeable contracts, or any kind of contract that will be deployed
                     * behind a proxy. Since proxied contracts do not make use of a constructor, it's common to move constructor logic to an
                     * external initializer function, usually called `initialize`. It then becomes necessary to protect this initializer
                     * function so it can only be called once. The {initializer} modifier provided by this contract will have this effect.
                     *
                     * The initialization functions use a version number. Once a version number is used, it is consumed and cannot be
                     * reused. This mechanism prevents re-execution of each "step" but allows the creation of new initialization steps in
                     * case an upgrade adds a module that needs to be initialized.
                     *
                     * For example:
                     *
                     * [.hljs-theme-light.nopadding]
                     * ```
                     * contract MyToken is ERC20Upgradeable {
                     *     function initialize() initializer public {
                     *         __ERC20_init("MyToken", "MTK");
                     *     }
                     * }
                     * contract MyTokenV2 is MyToken, ERC20PermitUpgradeable {
                     *     function initializeV2() reinitializer(2) public {
                     *         __ERC20Permit_init("MyToken");
                     *     }
                     * }
                     * ```
                     *
                     * TIP: To avoid leaving the proxy in an uninitialized state, the initializer function should be called as early as
                     * possible by providing the encoded function call as the `_data` argument to {ERC1967Proxy-constructor}.
                     *
                     * CAUTION: When used with inheritance, manual care must be taken to not invoke a parent initializer twice, or to ensure
                     * that all initializers are idempotent. This is not verified automatically as constructors are by Solidity.
                     *
                     * [CAUTION]
                     * ====
                     * Avoid leaving a contract uninitialized.
                     *
                     * An uninitialized contract can be taken over by an attacker. This applies to both a proxy and its implementation
                     * contract, which may impact the proxy. To prevent the implementation contract from being used, you should invoke
                     * the {_disableInitializers} function in the constructor to automatically lock it when it is deployed:
                     *
                     * [.hljs-theme-light.nopadding]
                     * ```
                     * /// @custom:oz-upgrades-unsafe-allow constructor
                     * constructor() {
                     *     _disableInitializers();
                     * }
                     * ```
                     * ====
                     */
                    abstract contract Initializable {
                        /**
                         * @dev Indicates that the contract has been initialized.
                         * @custom:oz-retyped-from bool
                         */
                        uint8 private _initialized;
                        /**
                         * @dev Indicates that the contract is in the process of being initialized.
                         */
                        bool private _initializing;
                        /**
                         * @dev Triggered when the contract has been initialized or reinitialized.
                         */
                        event Initialized(uint8 version);
                        /**
                         * @dev A modifier that defines a protected initializer function that can be invoked at most once. In its scope,
                         * `onlyInitializing` functions can be used to initialize parent contracts. Equivalent to `reinitializer(1)`.
                         */
                        modifier initializer() {
                            bool isTopLevelCall = !_initializing;
                            require(
                                (isTopLevelCall && _initialized < 1) || (!Address.isContract(address(this)) && _initialized == 1),
                                "Initializable: contract is already initialized"
                            );
                            _initialized = 1;
                            if (isTopLevelCall) {
                                _initializing = true;
                            }
                            _;
                            if (isTopLevelCall) {
                                _initializing = false;
                                emit Initialized(1);
                            }
                        }
                        /**
                         * @dev A modifier that defines a protected reinitializer function that can be invoked at most once, and only if the
                         * contract hasn't been initialized to a greater version before. In its scope, `onlyInitializing` functions can be
                         * used to initialize parent contracts.
                         *
                         * `initializer` is equivalent to `reinitializer(1)`, so a reinitializer may be used after the original
                         * initialization step. This is essential to configure modules that are added through upgrades and that require
                         * initialization.
                         *
                         * Note that versions can jump in increments greater than 1; this implies that if multiple reinitializers coexist in
                         * a contract, executing them in the right order is up to the developer or operator.
                         */
                        modifier reinitializer(uint8 version) {
                            require(!_initializing && _initialized < version, "Initializable: contract is already initialized");
                            _initialized = version;
                            _initializing = true;
                            _;
                            _initializing = false;
                            emit Initialized(version);
                        }
                        /**
                         * @dev Modifier to protect an initialization function so that it can only be invoked by functions with the
                         * {initializer} and {reinitializer} modifiers, directly or indirectly.
                         */
                        modifier onlyInitializing() {
                            require(_initializing, "Initializable: contract is not initializing");
                            _;
                        }
                        /**
                         * @dev Locks the contract, preventing any future reinitialization. This cannot be part of an initializer call.
                         * Calling this in the constructor of a contract will prevent that contract from being initialized or reinitialized
                         * to any version. It is recommended to use this to lock implementation contracts that are designed to be called
                         * through proxies.
                         */
                        function _disableInitializers() internal virtual {
                            require(!_initializing, "Initializable: contract is initializing");
                            if (_initialized < type(uint8).max) {
                                _initialized = type(uint8).max;
                                emit Initialized(type(uint8).max);
                            }
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    // OpenZeppelin Contracts (last updated v4.7.0) (token/ERC20/ERC20.sol)
                    pragma solidity ^0.8.0;
                    import "./IERC20.sol";
                    import "./extensions/IERC20Metadata.sol";
                    import "../../utils/Context.sol";
                    /**
                     * @dev Implementation of the {IERC20} interface.
                     *
                     * This implementation is agnostic to the way tokens are created. This means
                     * that a supply mechanism has to be added in a derived contract using {_mint}.
                     * For a generic mechanism see {ERC20PresetMinterPauser}.
                     *
                     * TIP: For a detailed writeup see our guide
                     * https://forum.zeppelin.solutions/t/how-to-implement-erc20-supply-mechanisms/226[How
                     * to implement supply mechanisms].
                     *
                     * We have followed general OpenZeppelin Contracts guidelines: functions revert
                     * instead returning `false` on failure. This behavior is nonetheless
                     * conventional and does not conflict with the expectations of ERC20
                     * applications.
                     *
                     * Additionally, an {Approval} event is emitted on calls to {transferFrom}.
                     * This allows applications to reconstruct the allowance for all accounts just
                     * by listening to said events. Other implementations of the EIP may not emit
                     * these events, as it isn't required by the specification.
                     *
                     * Finally, the non-standard {decreaseAllowance} and {increaseAllowance}
                     * functions have been added to mitigate the well-known issues around setting
                     * allowances. See {IERC20-approve}.
                     */
                    contract ERC20 is Context, IERC20, IERC20Metadata {
                        mapping(address => uint256) private _balances;
                        mapping(address => mapping(address => uint256)) private _allowances;
                        uint256 private _totalSupply;
                        string private _name;
                        string private _symbol;
                        /**
                         * @dev Sets the values for {name} and {symbol}.
                         *
                         * The default value of {decimals} is 18. To select a different value for
                         * {decimals} you should overload it.
                         *
                         * All two of these values are immutable: they can only be set once during
                         * construction.
                         */
                        constructor(string memory name_, string memory symbol_) {
                            _name = name_;
                            _symbol = symbol_;
                        }
                        /**
                         * @dev Returns the name of the token.
                         */
                        function name() public view virtual override returns (string memory) {
                            return _name;
                        }
                        /**
                         * @dev Returns the symbol of the token, usually a shorter version of the
                         * name.
                         */
                        function symbol() public view virtual override returns (string memory) {
                            return _symbol;
                        }
                        /**
                         * @dev Returns the number of decimals used to get its user representation.
                         * For example, if `decimals` equals `2`, a balance of `505` tokens should
                         * be displayed to a user as `5.05` (`505 / 10 ** 2`).
                         *
                         * Tokens usually opt for a value of 18, imitating the relationship between
                         * Ether and Wei. This is the value {ERC20} uses, unless this function is
                         * overridden;
                         *
                         * NOTE: This information is only used for _display_ purposes: it in
                         * no way affects any of the arithmetic of the contract, including
                         * {IERC20-balanceOf} and {IERC20-transfer}.
                         */
                        function decimals() public view virtual override returns (uint8) {
                            return 18;
                        }
                        /**
                         * @dev See {IERC20-totalSupply}.
                         */
                        function totalSupply() public view virtual override returns (uint256) {
                            return _totalSupply;
                        }
                        /**
                         * @dev See {IERC20-balanceOf}.
                         */
                        function balanceOf(address account) public view virtual override returns (uint256) {
                            return _balances[account];
                        }
                        /**
                         * @dev See {IERC20-transfer}.
                         *
                         * Requirements:
                         *
                         * - `to` cannot be the zero address.
                         * - the caller must have a balance of at least `amount`.
                         */
                        function transfer(address to, uint256 amount) public virtual override returns (bool) {
                            address owner = _msgSender();
                            _transfer(owner, to, amount);
                            return true;
                        }
                        /**
                         * @dev See {IERC20-allowance}.
                         */
                        function allowance(address owner, address spender) public view virtual override returns (uint256) {
                            return _allowances[owner][spender];
                        }
                        /**
                         * @dev See {IERC20-approve}.
                         *
                         * NOTE: If `amount` is the maximum `uint256`, the allowance is not updated on
                         * `transferFrom`. This is semantically equivalent to an infinite approval.
                         *
                         * Requirements:
                         *
                         * - `spender` cannot be the zero address.
                         */
                        function approve(address spender, uint256 amount) public virtual override returns (bool) {
                            address owner = _msgSender();
                            _approve(owner, spender, amount);
                            return true;
                        }
                        /**
                         * @dev See {IERC20-transferFrom}.
                         *
                         * Emits an {Approval} event indicating the updated allowance. This is not
                         * required by the EIP. See the note at the beginning of {ERC20}.
                         *
                         * NOTE: Does not update the allowance if the current allowance
                         * is the maximum `uint256`.
                         *
                         * Requirements:
                         *
                         * - `from` and `to` cannot be the zero address.
                         * - `from` must have a balance of at least `amount`.
                         * - the caller must have allowance for ``from``'s tokens of at least
                         * `amount`.
                         */
                        function transferFrom(
                            address from,
                            address to,
                            uint256 amount
                        ) public virtual override returns (bool) {
                            address spender = _msgSender();
                            _spendAllowance(from, spender, amount);
                            _transfer(from, to, amount);
                            return true;
                        }
                        /**
                         * @dev Atomically increases the allowance granted to `spender` by the caller.
                         *
                         * This is an alternative to {approve} that can be used as a mitigation for
                         * problems described in {IERC20-approve}.
                         *
                         * Emits an {Approval} event indicating the updated allowance.
                         *
                         * Requirements:
                         *
                         * - `spender` cannot be the zero address.
                         */
                        function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) {
                            address owner = _msgSender();
                            _approve(owner, spender, allowance(owner, spender) + addedValue);
                            return true;
                        }
                        /**
                         * @dev Atomically decreases the allowance granted to `spender` by the caller.
                         *
                         * This is an alternative to {approve} that can be used as a mitigation for
                         * problems described in {IERC20-approve}.
                         *
                         * Emits an {Approval} event indicating the updated allowance.
                         *
                         * Requirements:
                         *
                         * - `spender` cannot be the zero address.
                         * - `spender` must have allowance for the caller of at least
                         * `subtractedValue`.
                         */
                        function decreaseAllowance(address spender, uint256 subtractedValue) public virtual returns (bool) {
                            address owner = _msgSender();
                            uint256 currentAllowance = allowance(owner, spender);
                            require(currentAllowance >= subtractedValue, "ERC20: decreased allowance below zero");
                            unchecked {
                                _approve(owner, spender, currentAllowance - subtractedValue);
                            }
                            return true;
                        }
                        /**
                         * @dev Moves `amount` of tokens from `from` to `to`.
                         *
                         * This internal function is equivalent to {transfer}, and can be used to
                         * e.g. implement automatic token fees, slashing mechanisms, etc.
                         *
                         * Emits a {Transfer} event.
                         *
                         * Requirements:
                         *
                         * - `from` cannot be the zero address.
                         * - `to` cannot be the zero address.
                         * - `from` must have a balance of at least `amount`.
                         */
                        function _transfer(
                            address from,
                            address to,
                            uint256 amount
                        ) internal virtual {
                            require(from != address(0), "ERC20: transfer from the zero address");
                            require(to != address(0), "ERC20: transfer to the zero address");
                            _beforeTokenTransfer(from, to, amount);
                            uint256 fromBalance = _balances[from];
                            require(fromBalance >= amount, "ERC20: transfer amount exceeds balance");
                            unchecked {
                                _balances[from] = fromBalance - amount;
                            }
                            _balances[to] += amount;
                            emit Transfer(from, to, amount);
                            _afterTokenTransfer(from, to, amount);
                        }
                        /** @dev Creates `amount` tokens and assigns them to `account`, increasing
                         * the total supply.
                         *
                         * Emits a {Transfer} event with `from` set to the zero address.
                         *
                         * Requirements:
                         *
                         * - `account` cannot be the zero address.
                         */
                        function _mint(address account, uint256 amount) internal virtual {
                            require(account != address(0), "ERC20: mint to the zero address");
                            _beforeTokenTransfer(address(0), account, amount);
                            _totalSupply += amount;
                            _balances[account] += amount;
                            emit Transfer(address(0), account, amount);
                            _afterTokenTransfer(address(0), account, amount);
                        }
                        /**
                         * @dev Destroys `amount` tokens from `account`, reducing the
                         * total supply.
                         *
                         * Emits a {Transfer} event with `to` set to the zero address.
                         *
                         * Requirements:
                         *
                         * - `account` cannot be the zero address.
                         * - `account` must have at least `amount` tokens.
                         */
                        function _burn(address account, uint256 amount) internal virtual {
                            require(account != address(0), "ERC20: burn from the zero address");
                            _beforeTokenTransfer(account, address(0), amount);
                            uint256 accountBalance = _balances[account];
                            require(accountBalance >= amount, "ERC20: burn amount exceeds balance");
                            unchecked {
                                _balances[account] = accountBalance - amount;
                            }
                            _totalSupply -= amount;
                            emit Transfer(account, address(0), amount);
                            _afterTokenTransfer(account, address(0), amount);
                        }
                        /**
                         * @dev Sets `amount` as the allowance of `spender` over the `owner` s tokens.
                         *
                         * This internal function is equivalent to `approve`, and can be used to
                         * e.g. set automatic allowances for certain subsystems, etc.
                         *
                         * Emits an {Approval} event.
                         *
                         * Requirements:
                         *
                         * - `owner` cannot be the zero address.
                         * - `spender` cannot be the zero address.
                         */
                        function _approve(
                            address owner,
                            address spender,
                            uint256 amount
                        ) internal virtual {
                            require(owner != address(0), "ERC20: approve from the zero address");
                            require(spender != address(0), "ERC20: approve to the zero address");
                            _allowances[owner][spender] = amount;
                            emit Approval(owner, spender, amount);
                        }
                        /**
                         * @dev Updates `owner` s allowance for `spender` based on spent `amount`.
                         *
                         * Does not update the allowance amount in case of infinite allowance.
                         * Revert if not enough allowance is available.
                         *
                         * Might emit an {Approval} event.
                         */
                        function _spendAllowance(
                            address owner,
                            address spender,
                            uint256 amount
                        ) internal virtual {
                            uint256 currentAllowance = allowance(owner, spender);
                            if (currentAllowance != type(uint256).max) {
                                require(currentAllowance >= amount, "ERC20: insufficient allowance");
                                unchecked {
                                    _approve(owner, spender, currentAllowance - amount);
                                }
                            }
                        }
                        /**
                         * @dev Hook that is called before any transfer of tokens. This includes
                         * minting and burning.
                         *
                         * Calling conditions:
                         *
                         * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
                         * will be transferred to `to`.
                         * - when `from` is zero, `amount` tokens will be minted for `to`.
                         * - when `to` is zero, `amount` of ``from``'s tokens will be burned.
                         * - `from` and `to` are never both zero.
                         *
                         * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
                         */
                        function _beforeTokenTransfer(
                            address from,
                            address to,
                            uint256 amount
                        ) internal virtual {}
                        /**
                         * @dev Hook that is called after any transfer of tokens. This includes
                         * minting and burning.
                         *
                         * Calling conditions:
                         *
                         * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
                         * has been transferred to `to`.
                         * - when `from` is zero, `amount` tokens have been minted for `to`.
                         * - when `to` is zero, `amount` of ``from``'s tokens have been burned.
                         * - `from` and `to` are never both zero.
                         *
                         * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
                         */
                        function _afterTokenTransfer(
                            address from,
                            address to,
                            uint256 amount
                        ) internal virtual {}
                    }
                    // SPDX-License-Identifier: MIT
                    // OpenZeppelin Contracts (last updated v4.6.0) (token/ERC20/IERC20.sol)
                    pragma solidity ^0.8.0;
                    /**
                     * @dev Interface of the ERC20 standard as defined in the EIP.
                     */
                    interface IERC20 {
                        /**
                         * @dev Emitted when `value` tokens are moved from one account (`from`) to
                         * another (`to`).
                         *
                         * Note that `value` may be zero.
                         */
                        event Transfer(address indexed from, address indexed to, uint256 value);
                        /**
                         * @dev Emitted when the allowance of a `spender` for an `owner` is set by
                         * a call to {approve}. `value` is the new allowance.
                         */
                        event Approval(address indexed owner, address indexed spender, uint256 value);
                        /**
                         * @dev Returns the amount of tokens in existence.
                         */
                        function totalSupply() external view returns (uint256);
                        /**
                         * @dev Returns the amount of tokens owned by `account`.
                         */
                        function balanceOf(address account) external view returns (uint256);
                        /**
                         * @dev Moves `amount` tokens from the caller's account to `to`.
                         *
                         * Returns a boolean value indicating whether the operation succeeded.
                         *
                         * Emits a {Transfer} event.
                         */
                        function transfer(address to, uint256 amount) external returns (bool);
                        /**
                         * @dev Returns the remaining number of tokens that `spender` will be
                         * allowed to spend on behalf of `owner` through {transferFrom}. This is
                         * zero by default.
                         *
                         * This value changes when {approve} or {transferFrom} are called.
                         */
                        function allowance(address owner, address spender) external view returns (uint256);
                        /**
                         * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
                         *
                         * Returns a boolean value indicating whether the operation succeeded.
                         *
                         * IMPORTANT: Beware that changing an allowance with this method brings the risk
                         * that someone may use both the old and the new allowance by unfortunate
                         * transaction ordering. One possible solution to mitigate this race
                         * condition is to first reduce the spender's allowance to 0 and set the
                         * desired value afterwards:
                         * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
                         *
                         * Emits an {Approval} event.
                         */
                        function approve(address spender, uint256 amount) external returns (bool);
                        /**
                         * @dev Moves `amount` tokens from `from` to `to` using the
                         * allowance mechanism. `amount` is then deducted from the caller's
                         * allowance.
                         *
                         * Returns a boolean value indicating whether the operation succeeded.
                         *
                         * Emits a {Transfer} event.
                         */
                        function transferFrom(
                            address from,
                            address to,
                            uint256 amount
                        ) external returns (bool);
                    }
                    // SPDX-License-Identifier: MIT
                    // OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/IERC20Metadata.sol)
                    pragma solidity ^0.8.0;
                    import "../IERC20.sol";
                    /**
                     * @dev Interface for the optional metadata functions from the ERC20 standard.
                     *
                     * _Available since v4.1._
                     */
                    interface IERC20Metadata is IERC20 {
                        /**
                         * @dev Returns the name of the token.
                         */
                        function name() external view returns (string memory);
                        /**
                         * @dev Returns the symbol of the token.
                         */
                        function symbol() external view returns (string memory);
                        /**
                         * @dev Returns the decimals places of the token.
                         */
                        function decimals() external view returns (uint8);
                    }
                    // SPDX-License-Identifier: MIT
                    // OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/draft-IERC20Permit.sol)
                    pragma solidity ^0.8.0;
                    /**
                     * @dev Interface of the ERC20 Permit extension allowing approvals to be made via signatures, as defined in
                     * https://eips.ethereum.org/EIPS/eip-2612[EIP-2612].
                     *
                     * Adds the {permit} method, which can be used to change an account's ERC20 allowance (see {IERC20-allowance}) by
                     * presenting a message signed by the account. By not relying on {IERC20-approve}, the token holder account doesn't
                     * need to send a transaction, and thus is not required to hold Ether at all.
                     */
                    interface IERC20Permit {
                        /**
                         * @dev Sets `value` as the allowance of `spender` over ``owner``'s tokens,
                         * given ``owner``'s signed approval.
                         *
                         * IMPORTANT: The same issues {IERC20-approve} has related to transaction
                         * ordering also apply here.
                         *
                         * Emits an {Approval} event.
                         *
                         * Requirements:
                         *
                         * - `spender` cannot be the zero address.
                         * - `deadline` must be a timestamp in the future.
                         * - `v`, `r` and `s` must be a valid `secp256k1` signature from `owner`
                         * over the EIP712-formatted function arguments.
                         * - the signature must use ``owner``'s current nonce (see {nonces}).
                         *
                         * For more information on the signature format, see the
                         * https://eips.ethereum.org/EIPS/eip-2612#specification[relevant EIP
                         * section].
                         */
                        function permit(
                            address owner,
                            address spender,
                            uint256 value,
                            uint256 deadline,
                            uint8 v,
                            bytes32 r,
                            bytes32 s
                        ) external;
                        /**
                         * @dev Returns the current nonce for `owner`. This value must be
                         * included whenever a signature is generated for {permit}.
                         *
                         * Every successful call to {permit} increases ``owner``'s nonce by one. This
                         * prevents a signature from being used multiple times.
                         */
                        function nonces(address owner) external view returns (uint256);
                        /**
                         * @dev Returns the domain separator used in the encoding of the signature for {permit}, as defined by {EIP712}.
                         */
                        // solhint-disable-next-line func-name-mixedcase
                        function DOMAIN_SEPARATOR() external view returns (bytes32);
                    }
                    // SPDX-License-Identifier: MIT
                    // OpenZeppelin Contracts (last updated v4.7.0) (token/ERC20/utils/SafeERC20.sol)
                    pragma solidity ^0.8.0;
                    import "../IERC20.sol";
                    import "../extensions/draft-IERC20Permit.sol";
                    import "../../../utils/Address.sol";
                    /**
                     * @title SafeERC20
                     * @dev Wrappers around ERC20 operations that throw on failure (when the token
                     * contract returns false). Tokens that return no value (and instead revert or
                     * throw on failure) are also supported, non-reverting calls are assumed to be
                     * successful.
                     * To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract,
                     * which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
                     */
                    library SafeERC20 {
                        using Address for address;
                        function safeTransfer(
                            IERC20 token,
                            address to,
                            uint256 value
                        ) internal {
                            _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
                        }
                        function safeTransferFrom(
                            IERC20 token,
                            address from,
                            address to,
                            uint256 value
                        ) internal {
                            _callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
                        }
                        /**
                         * @dev Deprecated. This function has issues similar to the ones found in
                         * {IERC20-approve}, and its usage is discouraged.
                         *
                         * Whenever possible, use {safeIncreaseAllowance} and
                         * {safeDecreaseAllowance} instead.
                         */
                        function safeApprove(
                            IERC20 token,
                            address spender,
                            uint256 value
                        ) internal {
                            // safeApprove should only be called when setting an initial allowance,
                            // or when resetting it to zero. To increase and decrease it, use
                            // 'safeIncreaseAllowance' and 'safeDecreaseAllowance'
                            require(
                                (value == 0) || (token.allowance(address(this), spender) == 0),
                                "SafeERC20: approve from non-zero to non-zero allowance"
                            );
                            _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
                        }
                        function safeIncreaseAllowance(
                            IERC20 token,
                            address spender,
                            uint256 value
                        ) internal {
                            uint256 newAllowance = token.allowance(address(this), spender) + value;
                            _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
                        }
                        function safeDecreaseAllowance(
                            IERC20 token,
                            address spender,
                            uint256 value
                        ) internal {
                            unchecked {
                                uint256 oldAllowance = token.allowance(address(this), spender);
                                require(oldAllowance >= value, "SafeERC20: decreased allowance below zero");
                                uint256 newAllowance = oldAllowance - value;
                                _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
                            }
                        }
                        function safePermit(
                            IERC20Permit token,
                            address owner,
                            address spender,
                            uint256 value,
                            uint256 deadline,
                            uint8 v,
                            bytes32 r,
                            bytes32 s
                        ) internal {
                            uint256 nonceBefore = token.nonces(owner);
                            token.permit(owner, spender, value, deadline, v, r, s);
                            uint256 nonceAfter = token.nonces(owner);
                            require(nonceAfter == nonceBefore + 1, "SafeERC20: permit did not succeed");
                        }
                        /**
                         * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
                         * on the return value: the return value is optional (but if data is returned, it must not be false).
                         * @param token The token targeted by the call.
                         * @param data The call data (encoded using abi.encode or one of its variants).
                         */
                        function _callOptionalReturn(IERC20 token, bytes memory data) private {
                            // We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
                            // we're implementing it ourselves. We use {Address.functionCall} to perform this call, which verifies that
                            // the target address contains contract code and also asserts for success in the low-level call.
                            bytes memory returndata = address(token).functionCall(data, "SafeERC20: low-level call failed");
                            if (returndata.length > 0) {
                                // Return data is optional
                                require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
                            }
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    // OpenZeppelin Contracts (last updated v4.7.0) (utils/Address.sol)
                    pragma solidity ^0.8.1;
                    /**
                     * @dev Collection of functions related to the address type
                     */
                    library Address {
                        /**
                         * @dev Returns true if `account` is a contract.
                         *
                         * [IMPORTANT]
                         * ====
                         * It is unsafe to assume that an address for which this function returns
                         * false is an externally-owned account (EOA) and not a contract.
                         *
                         * Among others, `isContract` will return false for the following
                         * types of addresses:
                         *
                         *  - an externally-owned account
                         *  - a contract in construction
                         *  - an address where a contract will be created
                         *  - an address where a contract lived, but was destroyed
                         * ====
                         *
                         * [IMPORTANT]
                         * ====
                         * You shouldn't rely on `isContract` to protect against flash loan attacks!
                         *
                         * Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets
                         * like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract
                         * constructor.
                         * ====
                         */
                        function isContract(address account) internal view returns (bool) {
                            // This method relies on extcodesize/address.code.length, which returns 0
                            // for contracts in construction, since the code is only stored at the end
                            // of the constructor execution.
                            return account.code.length > 0;
                        }
                        /**
                         * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
                         * `recipient`, forwarding all available gas and reverting on errors.
                         *
                         * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
                         * of certain opcodes, possibly making contracts go over the 2300 gas limit
                         * imposed by `transfer`, making them unable to receive funds via
                         * `transfer`. {sendValue} removes this limitation.
                         *
                         * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
                         *
                         * IMPORTANT: because control is transferred to `recipient`, care must be
                         * taken to not create reentrancy vulnerabilities. Consider using
                         * {ReentrancyGuard} or the
                         * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
                         */
                        function sendValue(address payable recipient, uint256 amount) internal {
                            require(address(this).balance >= amount, "Address: insufficient balance");
                            (bool success, ) = recipient.call{value: amount}("");
                            require(success, "Address: unable to send value, recipient may have reverted");
                        }
                        /**
                         * @dev Performs a Solidity function call using a low level `call`. A
                         * plain `call` is an unsafe replacement for a function call: use this
                         * function instead.
                         *
                         * If `target` reverts with a revert reason, it is bubbled up by this
                         * function (like regular Solidity function calls).
                         *
                         * Returns the raw returned data. To convert to the expected return value,
                         * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
                         *
                         * Requirements:
                         *
                         * - `target` must be a contract.
                         * - calling `target` with `data` must not revert.
                         *
                         * _Available since v3.1._
                         */
                        function functionCall(address target, bytes memory data) internal returns (bytes memory) {
                            return functionCall(target, data, "Address: low-level call failed");
                        }
                        /**
                         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
                         * `errorMessage` as a fallback revert reason when `target` reverts.
                         *
                         * _Available since v3.1._
                         */
                        function functionCall(
                            address target,
                            bytes memory data,
                            string memory errorMessage
                        ) internal returns (bytes memory) {
                            return functionCallWithValue(target, data, 0, errorMessage);
                        }
                        /**
                         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
                         * but also transferring `value` wei to `target`.
                         *
                         * Requirements:
                         *
                         * - the calling contract must have an ETH balance of at least `value`.
                         * - the called Solidity function must be `payable`.
                         *
                         * _Available since v3.1._
                         */
                        function functionCallWithValue(
                            address target,
                            bytes memory data,
                            uint256 value
                        ) internal returns (bytes memory) {
                            return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
                        }
                        /**
                         * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
                         * with `errorMessage` as a fallback revert reason when `target` reverts.
                         *
                         * _Available since v3.1._
                         */
                        function functionCallWithValue(
                            address target,
                            bytes memory data,
                            uint256 value,
                            string memory errorMessage
                        ) internal returns (bytes memory) {
                            require(address(this).balance >= value, "Address: insufficient balance for call");
                            require(isContract(target), "Address: call to non-contract");
                            (bool success, bytes memory returndata) = target.call{value: value}(data);
                            return verifyCallResult(success, returndata, errorMessage);
                        }
                        /**
                         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
                         * but performing a static call.
                         *
                         * _Available since v3.3._
                         */
                        function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
                            return functionStaticCall(target, data, "Address: low-level static call failed");
                        }
                        /**
                         * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
                         * but performing a static call.
                         *
                         * _Available since v3.3._
                         */
                        function functionStaticCall(
                            address target,
                            bytes memory data,
                            string memory errorMessage
                        ) internal view returns (bytes memory) {
                            require(isContract(target), "Address: static call to non-contract");
                            (bool success, bytes memory returndata) = target.staticcall(data);
                            return verifyCallResult(success, returndata, errorMessage);
                        }
                        /**
                         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
                         * but performing a delegate call.
                         *
                         * _Available since v3.4._
                         */
                        function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
                            return functionDelegateCall(target, data, "Address: low-level delegate call failed");
                        }
                        /**
                         * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
                         * but performing a delegate call.
                         *
                         * _Available since v3.4._
                         */
                        function functionDelegateCall(
                            address target,
                            bytes memory data,
                            string memory errorMessage
                        ) internal returns (bytes memory) {
                            require(isContract(target), "Address: delegate call to non-contract");
                            (bool success, bytes memory returndata) = target.delegatecall(data);
                            return verifyCallResult(success, returndata, errorMessage);
                        }
                        /**
                         * @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the
                         * revert reason using the provided one.
                         *
                         * _Available since v4.3._
                         */
                        function verifyCallResult(
                            bool success,
                            bytes memory returndata,
                            string memory errorMessage
                        ) internal pure returns (bytes memory) {
                            if (success) {
                                return returndata;
                            } else {
                                // Look for revert reason and bubble it up if present
                                if (returndata.length > 0) {
                                    // The easiest way to bubble the revert reason is using memory via assembly
                                    /// @solidity memory-safe-assembly
                                    assembly {
                                        let returndata_size := mload(returndata)
                                        revert(add(32, returndata), returndata_size)
                                    }
                                } else {
                                    revert(errorMessage);
                                }
                            }
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    // OpenZeppelin Contracts v4.4.1 (utils/Context.sol)
                    pragma solidity ^0.8.0;
                    /**
                     * @dev Provides information about the current execution context, including the
                     * sender of the transaction and its data. While these are generally available
                     * via msg.sender and msg.data, they should not be accessed in such a direct
                     * manner, since when dealing with meta-transactions the account sending and
                     * paying for execution may not be the actual sender (as far as an application
                     * is concerned).
                     *
                     * This contract is only required for intermediate, library-like contracts.
                     */
                    abstract contract Context {
                        function _msgSender() internal view virtual returns (address) {
                            return msg.sender;
                        }
                        function _msgData() internal view virtual returns (bytes calldata) {
                            return msg.data;
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    // OpenZeppelin Contracts (last updated v4.7.0) (utils/Strings.sol)
                    pragma solidity ^0.8.0;
                    /**
                     * @dev String operations.
                     */
                    library Strings {
                        bytes16 private constant _HEX_SYMBOLS = "0123456789abcdef";
                        uint8 private constant _ADDRESS_LENGTH = 20;
                        /**
                         * @dev Converts a `uint256` to its ASCII `string` decimal representation.
                         */
                        function toString(uint256 value) internal pure returns (string memory) {
                            // Inspired by OraclizeAPI's implementation - MIT licence
                            // https://github.com/oraclize/ethereum-api/blob/b42146b063c7d6ee1358846c198246239e9360e8/oraclizeAPI_0.4.25.sol
                            if (value == 0) {
                                return "0";
                            }
                            uint256 temp = value;
                            uint256 digits;
                            while (temp != 0) {
                                digits++;
                                temp /= 10;
                            }
                            bytes memory buffer = new bytes(digits);
                            while (value != 0) {
                                digits -= 1;
                                buffer[digits] = bytes1(uint8(48 + uint256(value % 10)));
                                value /= 10;
                            }
                            return string(buffer);
                        }
                        /**
                         * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation.
                         */
                        function toHexString(uint256 value) internal pure returns (string memory) {
                            if (value == 0) {
                                return "0x00";
                            }
                            uint256 temp = value;
                            uint256 length = 0;
                            while (temp != 0) {
                                length++;
                                temp >>= 8;
                            }
                            return toHexString(value, length);
                        }
                        /**
                         * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation with fixed length.
                         */
                        function toHexString(uint256 value, uint256 length) internal pure returns (string memory) {
                            bytes memory buffer = new bytes(2 * length + 2);
                            buffer[0] = "0";
                            buffer[1] = "x";
                            for (uint256 i = 2 * length + 1; i > 1; --i) {
                                buffer[i] = _HEX_SYMBOLS[value & 0xf];
                                value >>= 4;
                            }
                            require(value == 0, "Strings: hex length insufficient");
                            return string(buffer);
                        }
                        /**
                         * @dev Converts an `address` with fixed length of 20 bytes to its not checksummed ASCII `string` hexadecimal representation.
                         */
                        function toHexString(address addr) internal pure returns (string memory) {
                            return toHexString(uint256(uint160(addr)), _ADDRESS_LENGTH);
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    // OpenZeppelin Contracts (last updated v4.7.2) (utils/introspection/ERC165Checker.sol)
                    pragma solidity ^0.8.0;
                    import "./IERC165.sol";
                    /**
                     * @dev Library used to query support of an interface declared via {IERC165}.
                     *
                     * Note that these functions return the actual result of the query: they do not
                     * `revert` if an interface is not supported. It is up to the caller to decide
                     * what to do in these cases.
                     */
                    library ERC165Checker {
                        // As per the EIP-165 spec, no interface should ever match 0xffffffff
                        bytes4 private constant _INTERFACE_ID_INVALID = 0xffffffff;
                        /**
                         * @dev Returns true if `account` supports the {IERC165} interface,
                         */
                        function supportsERC165(address account) internal view returns (bool) {
                            // Any contract that implements ERC165 must explicitly indicate support of
                            // InterfaceId_ERC165 and explicitly indicate non-support of InterfaceId_Invalid
                            return
                                _supportsERC165Interface(account, type(IERC165).interfaceId) &&
                                !_supportsERC165Interface(account, _INTERFACE_ID_INVALID);
                        }
                        /**
                         * @dev Returns true if `account` supports the interface defined by
                         * `interfaceId`. Support for {IERC165} itself is queried automatically.
                         *
                         * See {IERC165-supportsInterface}.
                         */
                        function supportsInterface(address account, bytes4 interfaceId) internal view returns (bool) {
                            // query support of both ERC165 as per the spec and support of _interfaceId
                            return supportsERC165(account) && _supportsERC165Interface(account, interfaceId);
                        }
                        /**
                         * @dev Returns a boolean array where each value corresponds to the
                         * interfaces passed in and whether they're supported or not. This allows
                         * you to batch check interfaces for a contract where your expectation
                         * is that some interfaces may not be supported.
                         *
                         * See {IERC165-supportsInterface}.
                         *
                         * _Available since v3.4._
                         */
                        function getSupportedInterfaces(address account, bytes4[] memory interfaceIds)
                            internal
                            view
                            returns (bool[] memory)
                        {
                            // an array of booleans corresponding to interfaceIds and whether they're supported or not
                            bool[] memory interfaceIdsSupported = new bool[](interfaceIds.length);
                            // query support of ERC165 itself
                            if (supportsERC165(account)) {
                                // query support of each interface in interfaceIds
                                for (uint256 i = 0; i < interfaceIds.length; i++) {
                                    interfaceIdsSupported[i] = _supportsERC165Interface(account, interfaceIds[i]);
                                }
                            }
                            return interfaceIdsSupported;
                        }
                        /**
                         * @dev Returns true if `account` supports all the interfaces defined in
                         * `interfaceIds`. Support for {IERC165} itself is queried automatically.
                         *
                         * Batch-querying can lead to gas savings by skipping repeated checks for
                         * {IERC165} support.
                         *
                         * See {IERC165-supportsInterface}.
                         */
                        function supportsAllInterfaces(address account, bytes4[] memory interfaceIds) internal view returns (bool) {
                            // query support of ERC165 itself
                            if (!supportsERC165(account)) {
                                return false;
                            }
                            // query support of each interface in _interfaceIds
                            for (uint256 i = 0; i < interfaceIds.length; i++) {
                                if (!_supportsERC165Interface(account, interfaceIds[i])) {
                                    return false;
                                }
                            }
                            // all interfaces supported
                            return true;
                        }
                        /**
                         * @notice Query if a contract implements an interface, does not check ERC165 support
                         * @param account The address of the contract to query for support of an interface
                         * @param interfaceId The interface identifier, as specified in ERC-165
                         * @return true if the contract at account indicates support of the interface with
                         * identifier interfaceId, false otherwise
                         * @dev Assumes that account contains a contract that supports ERC165, otherwise
                         * the behavior of this method is undefined. This precondition can be checked
                         * with {supportsERC165}.
                         * Interface identification is specified in ERC-165.
                         */
                        function _supportsERC165Interface(address account, bytes4 interfaceId) private view returns (bool) {
                            // prepare call
                            bytes memory encodedParams = abi.encodeWithSelector(IERC165.supportsInterface.selector, interfaceId);
                            // perform static call
                            bool success;
                            uint256 returnSize;
                            uint256 returnValue;
                            assembly {
                                success := staticcall(30000, account, add(encodedParams, 0x20), mload(encodedParams), 0x00, 0x20)
                                returnSize := returndatasize()
                                returnValue := mload(0x00)
                            }
                            return success && returnSize >= 0x20 && returnValue > 0;
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    // OpenZeppelin Contracts v4.4.1 (utils/introspection/IERC165.sol)
                    pragma solidity ^0.8.0;
                    /**
                     * @dev Interface of the ERC165 standard, as defined in the
                     * https://eips.ethereum.org/EIPS/eip-165[EIP].
                     *
                     * Implementers can declare support of contract interfaces, which can then be
                     * queried by others ({ERC165Checker}).
                     *
                     * For an implementation, see {ERC165}.
                     */
                    interface IERC165 {
                        /**
                         * @dev Returns true if this contract implements the interface defined by
                         * `interfaceId`. See the corresponding
                         * https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified[EIP section]
                         * to learn more about how these ids are created.
                         *
                         * This function call must use less than 30 000 gas.
                         */
                        function supportsInterface(bytes4 interfaceId) external view returns (bool);
                    }
                    // SPDX-License-Identifier: MIT
                    // OpenZeppelin Contracts (last updated v4.7.0) (utils/math/Math.sol)
                    pragma solidity ^0.8.0;
                    /**
                     * @dev Standard math utilities missing in the Solidity language.
                     */
                    library Math {
                        enum Rounding {
                            Down, // Toward negative infinity
                            Up, // Toward infinity
                            Zero // Toward zero
                        }
                        /**
                         * @dev Returns the largest of two numbers.
                         */
                        function max(uint256 a, uint256 b) internal pure returns (uint256) {
                            return a >= b ? a : b;
                        }
                        /**
                         * @dev Returns the smallest of two numbers.
                         */
                        function min(uint256 a, uint256 b) internal pure returns (uint256) {
                            return a < b ? a : b;
                        }
                        /**
                         * @dev Returns the average of two numbers. The result is rounded towards
                         * zero.
                         */
                        function average(uint256 a, uint256 b) internal pure returns (uint256) {
                            // (a + b) / 2 can overflow.
                            return (a & b) + (a ^ b) / 2;
                        }
                        /**
                         * @dev Returns the ceiling of the division of two numbers.
                         *
                         * This differs from standard division with `/` in that it rounds up instead
                         * of rounding down.
                         */
                        function ceilDiv(uint256 a, uint256 b) internal pure returns (uint256) {
                            // (a + b - 1) / b can overflow on addition, so we distribute.
                            return a == 0 ? 0 : (a - 1) / b + 1;
                        }
                        /**
                         * @notice Calculates floor(x * y / denominator) with full precision. Throws if result overflows a uint256 or denominator == 0
                         * @dev Original credit to Remco Bloemen under MIT license (https://xn--2-umb.com/21/muldiv)
                         * with further edits by Uniswap Labs also under MIT license.
                         */
                        function mulDiv(
                            uint256 x,
                            uint256 y,
                            uint256 denominator
                        ) internal pure returns (uint256 result) {
                            unchecked {
                                // 512-bit multiply [prod1 prod0] = x * y. Compute the product mod 2^256 and mod 2^256 - 1, then use
                                // use the Chinese Remainder Theorem to reconstruct the 512 bit result. The result is stored in two 256
                                // variables such that product = prod1 * 2^256 + prod0.
                                uint256 prod0; // Least significant 256 bits of the product
                                uint256 prod1; // Most significant 256 bits of the product
                                assembly {
                                    let mm := mulmod(x, y, not(0))
                                    prod0 := mul(x, y)
                                    prod1 := sub(sub(mm, prod0), lt(mm, prod0))
                                }
                                // Handle non-overflow cases, 256 by 256 division.
                                if (prod1 == 0) {
                                    return prod0 / denominator;
                                }
                                // Make sure the result is less than 2^256. Also prevents denominator == 0.
                                require(denominator > prod1);
                                ///////////////////////////////////////////////
                                // 512 by 256 division.
                                ///////////////////////////////////////////////
                                // Make division exact by subtracting the remainder from [prod1 prod0].
                                uint256 remainder;
                                assembly {
                                    // Compute remainder using mulmod.
                                    remainder := mulmod(x, y, denominator)
                                    // Subtract 256 bit number from 512 bit number.
                                    prod1 := sub(prod1, gt(remainder, prod0))
                                    prod0 := sub(prod0, remainder)
                                }
                                // Factor powers of two out of denominator and compute largest power of two divisor of denominator. Always >= 1.
                                // See https://cs.stackexchange.com/q/138556/92363.
                                // Does not overflow because the denominator cannot be zero at this stage in the function.
                                uint256 twos = denominator & (~denominator + 1);
                                assembly {
                                    // Divide denominator by twos.
                                    denominator := div(denominator, twos)
                                    // Divide [prod1 prod0] by twos.
                                    prod0 := div(prod0, twos)
                                    // Flip twos such that it is 2^256 / twos. If twos is zero, then it becomes one.
                                    twos := add(div(sub(0, twos), twos), 1)
                                }
                                // Shift in bits from prod1 into prod0.
                                prod0 |= prod1 * twos;
                                // Invert denominator mod 2^256. Now that denominator is an odd number, it has an inverse modulo 2^256 such
                                // that denominator * inv = 1 mod 2^256. Compute the inverse by starting with a seed that is correct for
                                // four bits. That is, denominator * inv = 1 mod 2^4.
                                uint256 inverse = (3 * denominator) ^ 2;
                                // Use the Newton-Raphson iteration to improve the precision. Thanks to Hensel's lifting lemma, this also works
                                // in modular arithmetic, doubling the correct bits in each step.
                                inverse *= 2 - denominator * inverse; // inverse mod 2^8
                                inverse *= 2 - denominator * inverse; // inverse mod 2^16
                                inverse *= 2 - denominator * inverse; // inverse mod 2^32
                                inverse *= 2 - denominator * inverse; // inverse mod 2^64
                                inverse *= 2 - denominator * inverse; // inverse mod 2^128
                                inverse *= 2 - denominator * inverse; // inverse mod 2^256
                                // Because the division is now exact we can divide by multiplying with the modular inverse of denominator.
                                // This will give us the correct result modulo 2^256. Since the preconditions guarantee that the outcome is
                                // less than 2^256, this is the final result. We don't need to compute the high bits of the result and prod1
                                // is no longer required.
                                result = prod0 * inverse;
                                return result;
                            }
                        }
                        /**
                         * @notice Calculates x * y / denominator with full precision, following the selected rounding direction.
                         */
                        function mulDiv(
                            uint256 x,
                            uint256 y,
                            uint256 denominator,
                            Rounding rounding
                        ) internal pure returns (uint256) {
                            uint256 result = mulDiv(x, y, denominator);
                            if (rounding == Rounding.Up && mulmod(x, y, denominator) > 0) {
                                result += 1;
                            }
                            return result;
                        }
                        /**
                         * @dev Returns the square root of a number. It the number is not a perfect square, the value is rounded down.
                         *
                         * Inspired by Henry S. Warren, Jr.'s "Hacker's Delight" (Chapter 11).
                         */
                        function sqrt(uint256 a) internal pure returns (uint256) {
                            if (a == 0) {
                                return 0;
                            }
                            // For our first guess, we get the biggest power of 2 which is smaller than the square root of the target.
                            // We know that the "msb" (most significant bit) of our target number `a` is a power of 2 such that we have
                            // `msb(a) <= a < 2*msb(a)`.
                            // We also know that `k`, the position of the most significant bit, is such that `msb(a) = 2**k`.
                            // This gives `2**k < a <= 2**(k+1)` → `2**(k/2) <= sqrt(a) < 2 ** (k/2+1)`.
                            // Using an algorithm similar to the msb conmputation, we are able to compute `result = 2**(k/2)` which is a
                            // good first aproximation of `sqrt(a)` with at least 1 correct bit.
                            uint256 result = 1;
                            uint256 x = a;
                            if (x >> 128 > 0) {
                                x >>= 128;
                                result <<= 64;
                            }
                            if (x >> 64 > 0) {
                                x >>= 64;
                                result <<= 32;
                            }
                            if (x >> 32 > 0) {
                                x >>= 32;
                                result <<= 16;
                            }
                            if (x >> 16 > 0) {
                                x >>= 16;
                                result <<= 8;
                            }
                            if (x >> 8 > 0) {
                                x >>= 8;
                                result <<= 4;
                            }
                            if (x >> 4 > 0) {
                                x >>= 4;
                                result <<= 2;
                            }
                            if (x >> 2 > 0) {
                                result <<= 1;
                            }
                            // At this point `result` is an estimation with one bit of precision. We know the true value is a uint128,
                            // since it is the square root of a uint256. Newton's method converges quadratically (precision doubles at
                            // every iteration). We thus need at most 7 iteration to turn our partial result with one bit of precision
                            // into the expected uint128 result.
                            unchecked {
                                result = (result + a / result) >> 1;
                                result = (result + a / result) >> 1;
                                result = (result + a / result) >> 1;
                                result = (result + a / result) >> 1;
                                result = (result + a / result) >> 1;
                                result = (result + a / result) >> 1;
                                result = (result + a / result) >> 1;
                                return min(result, a / result);
                            }
                        }
                        /**
                         * @notice Calculates sqrt(a), following the selected rounding direction.
                         */
                        function sqrt(uint256 a, Rounding rounding) internal pure returns (uint256) {
                            uint256 result = sqrt(a);
                            if (rounding == Rounding.Up && result * result < a) {
                                result += 1;
                            }
                            return result;
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    // OpenZeppelin Contracts (last updated v4.5.0) (utils/math/SignedMath.sol)
                    pragma solidity ^0.8.0;
                    /**
                     * @dev Standard signed math utilities missing in the Solidity language.
                     */
                    library SignedMath {
                        /**
                         * @dev Returns the largest of two signed numbers.
                         */
                        function max(int256 a, int256 b) internal pure returns (int256) {
                            return a >= b ? a : b;
                        }
                        /**
                         * @dev Returns the smallest of two signed numbers.
                         */
                        function min(int256 a, int256 b) internal pure returns (int256) {
                            return a < b ? a : b;
                        }
                        /**
                         * @dev Returns the average of two signed numbers without overflow.
                         * The result is rounded towards zero.
                         */
                        function average(int256 a, int256 b) internal pure returns (int256) {
                            // Formula from the book "Hacker's Delight"
                            int256 x = (a & b) + ((a ^ b) >> 1);
                            return x + (int256(uint256(x) >> 255) & (a ^ b));
                        }
                        /**
                         * @dev Returns the absolute unsigned value of a signed value.
                         */
                        function abs(int256 n) internal pure returns (uint256) {
                            unchecked {
                                // must be unchecked in order to support `n = type(int256).min`
                                return uint256(n >= 0 ? n : -n);
                            }
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    // OpenZeppelin Contracts (last updated v4.7.0) (proxy/utils/Initializable.sol)
                    pragma solidity ^0.8.2;
                    import "../../utils/AddressUpgradeable.sol";
                    /**
                     * @dev This is a base contract to aid in writing upgradeable contracts, or any kind of contract that will be deployed
                     * behind a proxy. Since proxied contracts do not make use of a constructor, it's common to move constructor logic to an
                     * external initializer function, usually called `initialize`. It then becomes necessary to protect this initializer
                     * function so it can only be called once. The {initializer} modifier provided by this contract will have this effect.
                     *
                     * The initialization functions use a version number. Once a version number is used, it is consumed and cannot be
                     * reused. This mechanism prevents re-execution of each "step" but allows the creation of new initialization steps in
                     * case an upgrade adds a module that needs to be initialized.
                     *
                     * For example:
                     *
                     * [.hljs-theme-light.nopadding]
                     * ```
                     * contract MyToken is ERC20Upgradeable {
                     *     function initialize() initializer public {
                     *         __ERC20_init("MyToken", "MTK");
                     *     }
                     * }
                     * contract MyTokenV2 is MyToken, ERC20PermitUpgradeable {
                     *     function initializeV2() reinitializer(2) public {
                     *         __ERC20Permit_init("MyToken");
                     *     }
                     * }
                     * ```
                     *
                     * TIP: To avoid leaving the proxy in an uninitialized state, the initializer function should be called as early as
                     * possible by providing the encoded function call as the `_data` argument to {ERC1967Proxy-constructor}.
                     *
                     * CAUTION: When used with inheritance, manual care must be taken to not invoke a parent initializer twice, or to ensure
                     * that all initializers are idempotent. This is not verified automatically as constructors are by Solidity.
                     *
                     * [CAUTION]
                     * ====
                     * Avoid leaving a contract uninitialized.
                     *
                     * An uninitialized contract can be taken over by an attacker. This applies to both a proxy and its implementation
                     * contract, which may impact the proxy. To prevent the implementation contract from being used, you should invoke
                     * the {_disableInitializers} function in the constructor to automatically lock it when it is deployed:
                     *
                     * [.hljs-theme-light.nopadding]
                     * ```
                     * /// @custom:oz-upgrades-unsafe-allow constructor
                     * constructor() {
                     *     _disableInitializers();
                     * }
                     * ```
                     * ====
                     */
                    abstract contract Initializable {
                        /**
                         * @dev Indicates that the contract has been initialized.
                         * @custom:oz-retyped-from bool
                         */
                        uint8 private _initialized;
                        /**
                         * @dev Indicates that the contract is in the process of being initialized.
                         */
                        bool private _initializing;
                        /**
                         * @dev Triggered when the contract has been initialized or reinitialized.
                         */
                        event Initialized(uint8 version);
                        /**
                         * @dev A modifier that defines a protected initializer function that can be invoked at most once. In its scope,
                         * `onlyInitializing` functions can be used to initialize parent contracts. Equivalent to `reinitializer(1)`.
                         */
                        modifier initializer() {
                            bool isTopLevelCall = !_initializing;
                            require(
                                (isTopLevelCall && _initialized < 1) || (!AddressUpgradeable.isContract(address(this)) && _initialized == 1),
                                "Initializable: contract is already initialized"
                            );
                            _initialized = 1;
                            if (isTopLevelCall) {
                                _initializing = true;
                            }
                            _;
                            if (isTopLevelCall) {
                                _initializing = false;
                                emit Initialized(1);
                            }
                        }
                        /**
                         * @dev A modifier that defines a protected reinitializer function that can be invoked at most once, and only if the
                         * contract hasn't been initialized to a greater version before. In its scope, `onlyInitializing` functions can be
                         * used to initialize parent contracts.
                         *
                         * `initializer` is equivalent to `reinitializer(1)`, so a reinitializer may be used after the original
                         * initialization step. This is essential to configure modules that are added through upgrades and that require
                         * initialization.
                         *
                         * Note that versions can jump in increments greater than 1; this implies that if multiple reinitializers coexist in
                         * a contract, executing them in the right order is up to the developer or operator.
                         */
                        modifier reinitializer(uint8 version) {
                            require(!_initializing && _initialized < version, "Initializable: contract is already initialized");
                            _initialized = version;
                            _initializing = true;
                            _;
                            _initializing = false;
                            emit Initialized(version);
                        }
                        /**
                         * @dev Modifier to protect an initialization function so that it can only be invoked by functions with the
                         * {initializer} and {reinitializer} modifiers, directly or indirectly.
                         */
                        modifier onlyInitializing() {
                            require(_initializing, "Initializable: contract is not initializing");
                            _;
                        }
                        /**
                         * @dev Locks the contract, preventing any future reinitialization. This cannot be part of an initializer call.
                         * Calling this in the constructor of a contract will prevent that contract from being initialized or reinitialized
                         * to any version. It is recommended to use this to lock implementation contracts that are designed to be called
                         * through proxies.
                         */
                        function _disableInitializers() internal virtual {
                            require(!_initializing, "Initializable: contract is initializing");
                            if (_initialized < type(uint8).max) {
                                _initialized = type(uint8).max;
                                emit Initialized(type(uint8).max);
                            }
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    // OpenZeppelin Contracts (last updated v4.7.0) (utils/Address.sol)
                    pragma solidity ^0.8.1;
                    /**
                     * @dev Collection of functions related to the address type
                     */
                    library AddressUpgradeable {
                        /**
                         * @dev Returns true if `account` is a contract.
                         *
                         * [IMPORTANT]
                         * ====
                         * It is unsafe to assume that an address for which this function returns
                         * false is an externally-owned account (EOA) and not a contract.
                         *
                         * Among others, `isContract` will return false for the following
                         * types of addresses:
                         *
                         *  - an externally-owned account
                         *  - a contract in construction
                         *  - an address where a contract will be created
                         *  - an address where a contract lived, but was destroyed
                         * ====
                         *
                         * [IMPORTANT]
                         * ====
                         * You shouldn't rely on `isContract` to protect against flash loan attacks!
                         *
                         * Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets
                         * like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract
                         * constructor.
                         * ====
                         */
                        function isContract(address account) internal view returns (bool) {
                            // This method relies on extcodesize/address.code.length, which returns 0
                            // for contracts in construction, since the code is only stored at the end
                            // of the constructor execution.
                            return account.code.length > 0;
                        }
                        /**
                         * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
                         * `recipient`, forwarding all available gas and reverting on errors.
                         *
                         * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
                         * of certain opcodes, possibly making contracts go over the 2300 gas limit
                         * imposed by `transfer`, making them unable to receive funds via
                         * `transfer`. {sendValue} removes this limitation.
                         *
                         * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
                         *
                         * IMPORTANT: because control is transferred to `recipient`, care must be
                         * taken to not create reentrancy vulnerabilities. Consider using
                         * {ReentrancyGuard} or the
                         * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
                         */
                        function sendValue(address payable recipient, uint256 amount) internal {
                            require(address(this).balance >= amount, "Address: insufficient balance");
                            (bool success, ) = recipient.call{value: amount}("");
                            require(success, "Address: unable to send value, recipient may have reverted");
                        }
                        /**
                         * @dev Performs a Solidity function call using a low level `call`. A
                         * plain `call` is an unsafe replacement for a function call: use this
                         * function instead.
                         *
                         * If `target` reverts with a revert reason, it is bubbled up by this
                         * function (like regular Solidity function calls).
                         *
                         * Returns the raw returned data. To convert to the expected return value,
                         * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
                         *
                         * Requirements:
                         *
                         * - `target` must be a contract.
                         * - calling `target` with `data` must not revert.
                         *
                         * _Available since v3.1._
                         */
                        function functionCall(address target, bytes memory data) internal returns (bytes memory) {
                            return functionCall(target, data, "Address: low-level call failed");
                        }
                        /**
                         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
                         * `errorMessage` as a fallback revert reason when `target` reverts.
                         *
                         * _Available since v3.1._
                         */
                        function functionCall(
                            address target,
                            bytes memory data,
                            string memory errorMessage
                        ) internal returns (bytes memory) {
                            return functionCallWithValue(target, data, 0, errorMessage);
                        }
                        /**
                         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
                         * but also transferring `value` wei to `target`.
                         *
                         * Requirements:
                         *
                         * - the calling contract must have an ETH balance of at least `value`.
                         * - the called Solidity function must be `payable`.
                         *
                         * _Available since v3.1._
                         */
                        function functionCallWithValue(
                            address target,
                            bytes memory data,
                            uint256 value
                        ) internal returns (bytes memory) {
                            return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
                        }
                        /**
                         * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
                         * with `errorMessage` as a fallback revert reason when `target` reverts.
                         *
                         * _Available since v3.1._
                         */
                        function functionCallWithValue(
                            address target,
                            bytes memory data,
                            uint256 value,
                            string memory errorMessage
                        ) internal returns (bytes memory) {
                            require(address(this).balance >= value, "Address: insufficient balance for call");
                            require(isContract(target), "Address: call to non-contract");
                            (bool success, bytes memory returndata) = target.call{value: value}(data);
                            return verifyCallResult(success, returndata, errorMessage);
                        }
                        /**
                         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
                         * but performing a static call.
                         *
                         * _Available since v3.3._
                         */
                        function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
                            return functionStaticCall(target, data, "Address: low-level static call failed");
                        }
                        /**
                         * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
                         * but performing a static call.
                         *
                         * _Available since v3.3._
                         */
                        function functionStaticCall(
                            address target,
                            bytes memory data,
                            string memory errorMessage
                        ) internal view returns (bytes memory) {
                            require(isContract(target), "Address: static call to non-contract");
                            (bool success, bytes memory returndata) = target.staticcall(data);
                            return verifyCallResult(success, returndata, errorMessage);
                        }
                        /**
                         * @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the
                         * revert reason using the provided one.
                         *
                         * _Available since v4.3._
                         */
                        function verifyCallResult(
                            bool success,
                            bytes memory returndata,
                            string memory errorMessage
                        ) internal pure returns (bytes memory) {
                            if (success) {
                                return returndata;
                            } else {
                                // Look for revert reason and bubble it up if present
                                if (returndata.length > 0) {
                                    // The easiest way to bubble the revert reason is using memory via assembly
                                    /// @solidity memory-safe-assembly
                                    assembly {
                                        let returndata_size := mload(returndata)
                                        revert(add(32, returndata), returndata_size)
                                    }
                                } else {
                                    revert(errorMessage);
                                }
                            }
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    pragma solidity >=0.8.0;
                    /// @notice Arithmetic library with operations for fixed-point numbers.
                    /// @author Solmate (https://github.com/Rari-Capital/solmate/blob/main/src/utils/FixedPointMathLib.sol)
                    library FixedPointMathLib {
                        /*//////////////////////////////////////////////////////////////
                                        SIMPLIFIED FIXED POINT OPERATIONS
                        //////////////////////////////////////////////////////////////*/
                        uint256 internal constant WAD = 1e18; // The scalar of ETH and most ERC20s.
                        function mulWadDown(uint256 x, uint256 y) internal pure returns (uint256) {
                            return mulDivDown(x, y, WAD); // Equivalent to (x * y) / WAD rounded down.
                        }
                        function mulWadUp(uint256 x, uint256 y) internal pure returns (uint256) {
                            return mulDivUp(x, y, WAD); // Equivalent to (x * y) / WAD rounded up.
                        }
                        function divWadDown(uint256 x, uint256 y) internal pure returns (uint256) {
                            return mulDivDown(x, WAD, y); // Equivalent to (x * WAD) / y rounded down.
                        }
                        function divWadUp(uint256 x, uint256 y) internal pure returns (uint256) {
                            return mulDivUp(x, WAD, y); // Equivalent to (x * WAD) / y rounded up.
                        }
                        function powWad(int256 x, int256 y) internal pure returns (int256) {
                            // Equivalent to x to the power of y because x ** y = (e ** ln(x)) ** y = e ** (ln(x) * y)
                            return expWad((lnWad(x) * y) / int256(WAD)); // Using ln(x) means x must be greater than 0.
                        }
                        function expWad(int256 x) internal pure returns (int256 r) {
                            unchecked {
                                // When the result is < 0.5 we return zero. This happens when
                                // x <= floor(log(0.5e18) * 1e18) ~ -42e18
                                if (x <= -42139678854452767551) return 0;
                                // When the result is > (2**255 - 1) / 1e18 we can not represent it as an
                                // int. This happens when x >= floor(log((2**255 - 1) / 1e18) * 1e18) ~ 135.
                                if (x >= 135305999368893231589) revert("EXP_OVERFLOW");
                                // x is now in the range (-42, 136) * 1e18. Convert to (-42, 136) * 2**96
                                // for more intermediate precision and a binary basis. This base conversion
                                // is a multiplication by 1e18 / 2**96 = 5**18 / 2**78.
                                x = (x << 78) / 5**18;
                                // Reduce range of x to (-½ ln 2, ½ ln 2) * 2**96 by factoring out powers
                                // of two such that exp(x) = exp(x') * 2**k, where k is an integer.
                                // Solving this gives k = round(x / log(2)) and x' = x - k * log(2).
                                int256 k = ((x << 96) / 54916777467707473351141471128 + 2**95) >> 96;
                                x = x - k * 54916777467707473351141471128;
                                // k is in the range [-61, 195].
                                // Evaluate using a (6, 7)-term rational approximation.
                                // p is made monic, we'll multiply by a scale factor later.
                                int256 y = x + 1346386616545796478920950773328;
                                y = ((y * x) >> 96) + 57155421227552351082224309758442;
                                int256 p = y + x - 94201549194550492254356042504812;
                                p = ((p * y) >> 96) + 28719021644029726153956944680412240;
                                p = p * x + (4385272521454847904659076985693276 << 96);
                                // We leave p in 2**192 basis so we don't need to scale it back up for the division.
                                int256 q = x - 2855989394907223263936484059900;
                                q = ((q * x) >> 96) + 50020603652535783019961831881945;
                                q = ((q * x) >> 96) - 533845033583426703283633433725380;
                                q = ((q * x) >> 96) + 3604857256930695427073651918091429;
                                q = ((q * x) >> 96) - 14423608567350463180887372962807573;
                                q = ((q * x) >> 96) + 26449188498355588339934803723976023;
                                assembly {
                                    // Div in assembly because solidity adds a zero check despite the unchecked.
                                    // The q polynomial won't have zeros in the domain as all its roots are complex.
                                    // No scaling is necessary because p is already 2**96 too large.
                                    r := sdiv(p, q)
                                }
                                // r should be in the range (0.09, 0.25) * 2**96.
                                // We now need to multiply r by:
                                // * the scale factor s = ~6.031367120.
                                // * the 2**k factor from the range reduction.
                                // * the 1e18 / 2**96 factor for base conversion.
                                // We do this all at once, with an intermediate result in 2**213
                                // basis, so the final right shift is always by a positive amount.
                                r = int256((uint256(r) * 3822833074963236453042738258902158003155416615667) >> uint256(195 - k));
                            }
                        }
                        function lnWad(int256 x) internal pure returns (int256 r) {
                            unchecked {
                                require(x > 0, "UNDEFINED");
                                // We want to convert x from 10**18 fixed point to 2**96 fixed point.
                                // We do this by multiplying by 2**96 / 10**18. But since
                                // ln(x * C) = ln(x) + ln(C), we can simply do nothing here
                                // and add ln(2**96 / 10**18) at the end.
                                // Reduce range of x to (1, 2) * 2**96
                                // ln(2^k * x) = k * ln(2) + ln(x)
                                int256 k = int256(log2(uint256(x))) - 96;
                                x <<= uint256(159 - k);
                                x = int256(uint256(x) >> 159);
                                // Evaluate using a (8, 8)-term rational approximation.
                                // p is made monic, we will multiply by a scale factor later.
                                int256 p = x + 3273285459638523848632254066296;
                                p = ((p * x) >> 96) + 24828157081833163892658089445524;
                                p = ((p * x) >> 96) + 43456485725739037958740375743393;
                                p = ((p * x) >> 96) - 11111509109440967052023855526967;
                                p = ((p * x) >> 96) - 45023709667254063763336534515857;
                                p = ((p * x) >> 96) - 14706773417378608786704636184526;
                                p = p * x - (795164235651350426258249787498 << 96);
                                // We leave p in 2**192 basis so we don't need to scale it back up for the division.
                                // q is monic by convention.
                                int256 q = x + 5573035233440673466300451813936;
                                q = ((q * x) >> 96) + 71694874799317883764090561454958;
                                q = ((q * x) >> 96) + 283447036172924575727196451306956;
                                q = ((q * x) >> 96) + 401686690394027663651624208769553;
                                q = ((q * x) >> 96) + 204048457590392012362485061816622;
                                q = ((q * x) >> 96) + 31853899698501571402653359427138;
                                q = ((q * x) >> 96) + 909429971244387300277376558375;
                                assembly {
                                    // Div in assembly because solidity adds a zero check despite the unchecked.
                                    // The q polynomial is known not to have zeros in the domain.
                                    // No scaling required because p is already 2**96 too large.
                                    r := sdiv(p, q)
                                }
                                // r is in the range (0, 0.125) * 2**96
                                // Finalization, we need to:
                                // * multiply by the scale factor s = 5.549…
                                // * add ln(2**96 / 10**18)
                                // * add k * ln(2)
                                // * multiply by 10**18 / 2**96 = 5**18 >> 78
                                // mul s * 5e18 * 2**96, base is now 5**18 * 2**192
                                r *= 1677202110996718588342820967067443963516166;
                                // add ln(2) * k * 5e18 * 2**192
                                r += 16597577552685614221487285958193947469193820559219878177908093499208371 * k;
                                // add ln(2**96 / 10**18) * 5e18 * 2**192
                                r += 600920179829731861736702779321621459595472258049074101567377883020018308;
                                // base conversion: mul 2**18 / 2**192
                                r >>= 174;
                            }
                        }
                        /*//////////////////////////////////////////////////////////////
                                        LOW LEVEL FIXED POINT OPERATIONS
                        //////////////////////////////////////////////////////////////*/
                        function mulDivDown(
                            uint256 x,
                            uint256 y,
                            uint256 denominator
                        ) internal pure returns (uint256 z) {
                            assembly {
                                // Store x * y in z for now.
                                z := mul(x, y)
                                // Equivalent to require(denominator != 0 && (x == 0 || (x * y) / x == y))
                                if iszero(and(iszero(iszero(denominator)), or(iszero(x), eq(div(z, x), y)))) {
                                    revert(0, 0)
                                }
                                // Divide z by the denominator.
                                z := div(z, denominator)
                            }
                        }
                        function mulDivUp(
                            uint256 x,
                            uint256 y,
                            uint256 denominator
                        ) internal pure returns (uint256 z) {
                            assembly {
                                // Store x * y in z for now.
                                z := mul(x, y)
                                // Equivalent to require(denominator != 0 && (x == 0 || (x * y) / x == y))
                                if iszero(and(iszero(iszero(denominator)), or(iszero(x), eq(div(z, x), y)))) {
                                    revert(0, 0)
                                }
                                // First, divide z - 1 by the denominator and add 1.
                                // We allow z - 1 to underflow if z is 0, because we multiply the
                                // end result by 0 if z is zero, ensuring we return 0 if z is zero.
                                z := mul(iszero(iszero(z)), add(div(sub(z, 1), denominator), 1))
                            }
                        }
                        function rpow(
                            uint256 x,
                            uint256 n,
                            uint256 scalar
                        ) internal pure returns (uint256 z) {
                            assembly {
                                switch x
                                case 0 {
                                    switch n
                                    case 0 {
                                        // 0 ** 0 = 1
                                        z := scalar
                                    }
                                    default {
                                        // 0 ** n = 0
                                        z := 0
                                    }
                                }
                                default {
                                    switch mod(n, 2)
                                    case 0 {
                                        // If n is even, store scalar in z for now.
                                        z := scalar
                                    }
                                    default {
                                        // If n is odd, store x in z for now.
                                        z := x
                                    }
                                    // Shifting right by 1 is like dividing by 2.
                                    let half := shr(1, scalar)
                                    for {
                                        // Shift n right by 1 before looping to halve it.
                                        n := shr(1, n)
                                    } n {
                                        // Shift n right by 1 each iteration to halve it.
                                        n := shr(1, n)
                                    } {
                                        // Revert immediately if x ** 2 would overflow.
                                        // Equivalent to iszero(eq(div(xx, x), x)) here.
                                        if shr(128, x) {
                                            revert(0, 0)
                                        }
                                        // Store x squared.
                                        let xx := mul(x, x)
                                        // Round to the nearest number.
                                        let xxRound := add(xx, half)
                                        // Revert if xx + half overflowed.
                                        if lt(xxRound, xx) {
                                            revert(0, 0)
                                        }
                                        // Set x to scaled xxRound.
                                        x := div(xxRound, scalar)
                                        // If n is even:
                                        if mod(n, 2) {
                                            // Compute z * x.
                                            let zx := mul(z, x)
                                            // If z * x overflowed:
                                            if iszero(eq(div(zx, x), z)) {
                                                // Revert if x is non-zero.
                                                if iszero(iszero(x)) {
                                                    revert(0, 0)
                                                }
                                            }
                                            // Round to the nearest number.
                                            let zxRound := add(zx, half)
                                            // Revert if zx + half overflowed.
                                            if lt(zxRound, zx) {
                                                revert(0, 0)
                                            }
                                            // Return properly scaled zxRound.
                                            z := div(zxRound, scalar)
                                        }
                                    }
                                }
                            }
                        }
                        /*//////////////////////////////////////////////////////////////
                                            GENERAL NUMBER UTILITIES
                        //////////////////////////////////////////////////////////////*/
                        function sqrt(uint256 x) internal pure returns (uint256 z) {
                            assembly {
                                let y := x // We start y at x, which will help us make our initial estimate.
                                z := 181 // The "correct" value is 1, but this saves a multiplication later.
                                // This segment is to get a reasonable initial estimate for the Babylonian method. With a bad
                                // start, the correct # of bits increases ~linearly each iteration instead of ~quadratically.
                                // We check y >= 2^(k + 8) but shift right by k bits
                                // each branch to ensure that if x >= 256, then y >= 256.
                                if iszero(lt(y, 0x10000000000000000000000000000000000)) {
                                    y := shr(128, y)
                                    z := shl(64, z)
                                }
                                if iszero(lt(y, 0x1000000000000000000)) {
                                    y := shr(64, y)
                                    z := shl(32, z)
                                }
                                if iszero(lt(y, 0x10000000000)) {
                                    y := shr(32, y)
                                    z := shl(16, z)
                                }
                                if iszero(lt(y, 0x1000000)) {
                                    y := shr(16, y)
                                    z := shl(8, z)
                                }
                                // Goal was to get z*z*y within a small factor of x. More iterations could
                                // get y in a tighter range. Currently, we will have y in [256, 256*2^16).
                                // We ensured y >= 256 so that the relative difference between y and y+1 is small.
                                // That's not possible if x < 256 but we can just verify those cases exhaustively.
                                // Now, z*z*y <= x < z*z*(y+1), and y <= 2^(16+8), and either y >= 256, or x < 256.
                                // Correctness can be checked exhaustively for x < 256, so we assume y >= 256.
                                // Then z*sqrt(y) is within sqrt(257)/sqrt(256) of sqrt(x), or about 20bps.
                                // For s in the range [1/256, 256], the estimate f(s) = (181/1024) * (s+1) is in the range
                                // (1/2.84 * sqrt(s), 2.84 * sqrt(s)), with largest error when s = 1 and when s = 256 or 1/256.
                                // Since y is in [256, 256*2^16), let a = y/65536, so that a is in [1/256, 256). Then we can estimate
                                // sqrt(y) using sqrt(65536) * 181/1024 * (a + 1) = 181/4 * (y + 65536)/65536 = 181 * (y + 65536)/2^18.
                                // There is no overflow risk here since y < 2^136 after the first branch above.
                                z := shr(18, mul(z, add(y, 65536))) // A mul() is saved from starting z at 181.
                                // Given the worst case multiplicative error of 2.84 above, 7 iterations should be enough.
                                z := shr(1, add(z, div(x, z)))
                                z := shr(1, add(z, div(x, z)))
                                z := shr(1, add(z, div(x, z)))
                                z := shr(1, add(z, div(x, z)))
                                z := shr(1, add(z, div(x, z)))
                                z := shr(1, add(z, div(x, z)))
                                z := shr(1, add(z, div(x, z)))
                                // If x+1 is a perfect square, the Babylonian method cycles between
                                // floor(sqrt(x)) and ceil(sqrt(x)). This statement ensures we return floor.
                                // See: https://en.wikipedia.org/wiki/Integer_square_root#Using_only_integer_division
                                // Since the ceil is rare, we save gas on the assignment and repeat division in the rare case.
                                // If you don't care whether the floor or ceil square root is returned, you can remove this statement.
                                z := sub(z, lt(div(x, z), z))
                            }
                        }
                        function log2(uint256 x) internal pure returns (uint256 r) {
                            require(x > 0, "UNDEFINED");
                            assembly {
                                r := shl(7, lt(0xffffffffffffffffffffffffffffffff, x))
                                r := or(r, shl(6, lt(0xffffffffffffffff, shr(r, x))))
                                r := or(r, shl(5, lt(0xffffffff, shr(r, x))))
                                r := or(r, shl(4, lt(0xffff, shr(r, x))))
                                r := or(r, shl(3, lt(0xff, shr(r, x))))
                                r := or(r, shl(2, lt(0xf, shr(r, x))))
                                r := or(r, shl(1, lt(0x3, shr(r, x))))
                                r := or(r, lt(0x1, shr(r, x)))
                            }
                        }
                    }
                    

                    File 7 of 11: FiatTokenV2_2
                    /**
                     * SPDX-License-Identifier: Apache-2.0
                     *
                     * Copyright (c) 2023, Circle Internet Financial, LLC.
                     *
                     * Licensed under the Apache License, Version 2.0 (the "License");
                     * you may not use this file except in compliance with the License.
                     * You may obtain a copy of the License at
                     *
                     * http://www.apache.org/licenses/LICENSE-2.0
                     *
                     * Unless required by applicable law or agreed to in writing, software
                     * distributed under the License is distributed on an "AS IS" BASIS,
                     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
                     * See the License for the specific language governing permissions and
                     * limitations under the License.
                     */
                    pragma solidity 0.6.12;
                    import { EIP712Domain } from "./EIP712Domain.sol"; // solhint-disable-line no-unused-import
                    import { Blacklistable } from "../v1/Blacklistable.sol"; // solhint-disable-line no-unused-import
                    import { FiatTokenV1 } from "../v1/FiatTokenV1.sol"; // solhint-disable-line no-unused-import
                    import { FiatTokenV2 } from "./FiatTokenV2.sol"; // solhint-disable-line no-unused-import
                    import { FiatTokenV2_1 } from "./FiatTokenV2_1.sol";
                    import { EIP712 } from "../util/EIP712.sol";
                    // solhint-disable func-name-mixedcase
                    /**
                     * @title FiatToken V2.2
                     * @notice ERC20 Token backed by fiat reserves, version 2.2
                     */
                    contract FiatTokenV2_2 is FiatTokenV2_1 {
                        /**
                         * @notice Initialize v2.2
                         * @param accountsToBlacklist   A list of accounts to migrate from the old blacklist
                         * @param newSymbol             New token symbol
                         * data structure to the new blacklist data structure.
                         */
                        function initializeV2_2(
                            address[] calldata accountsToBlacklist,
                            string calldata newSymbol
                        ) external {
                            // solhint-disable-next-line reason-string
                            require(_initializedVersion == 2);
                            // Update fiat token symbol
                            symbol = newSymbol;
                            // Add previously blacklisted accounts to the new blacklist data structure
                            // and remove them from the old blacklist data structure.
                            for (uint256 i = 0; i < accountsToBlacklist.length; i++) {
                                require(
                                    _deprecatedBlacklisted[accountsToBlacklist[i]],
                                    "FiatTokenV2_2: Blacklisting previously unblacklisted account!"
                                );
                                _blacklist(accountsToBlacklist[i]);
                                delete _deprecatedBlacklisted[accountsToBlacklist[i]];
                            }
                            _blacklist(address(this));
                            delete _deprecatedBlacklisted[address(this)];
                            _initializedVersion = 3;
                        }
                        /**
                         * @dev Internal function to get the current chain id.
                         * @return The current chain id.
                         */
                        function _chainId() internal virtual view returns (uint256) {
                            uint256 chainId;
                            assembly {
                                chainId := chainid()
                            }
                            return chainId;
                        }
                        /**
                         * @inheritdoc EIP712Domain
                         */
                        function _domainSeparator() internal override view returns (bytes32) {
                            return EIP712.makeDomainSeparator(name, "2", _chainId());
                        }
                        /**
                         * @notice Update allowance with a signed permit
                         * @dev EOA wallet signatures should be packed in the order of r, s, v.
                         * @param owner       Token owner's address (Authorizer)
                         * @param spender     Spender's address
                         * @param value       Amount of allowance
                         * @param deadline    The time at which the signature expires (unix time), or max uint256 value to signal no expiration
                         * @param signature   Signature bytes signed by an EOA wallet or a contract wallet
                         */
                        function permit(
                            address owner,
                            address spender,
                            uint256 value,
                            uint256 deadline,
                            bytes memory signature
                        ) external whenNotPaused {
                            _permit(owner, spender, value, deadline, signature);
                        }
                        /**
                         * @notice Execute a transfer with a signed authorization
                         * @dev EOA wallet signatures should be packed in the order of r, s, v.
                         * @param from          Payer's address (Authorizer)
                         * @param to            Payee's address
                         * @param value         Amount to be transferred
                         * @param validAfter    The time after which this is valid (unix time)
                         * @param validBefore   The time before which this is valid (unix time)
                         * @param nonce         Unique nonce
                         * @param signature     Signature bytes signed by an EOA wallet or a contract wallet
                         */
                        function transferWithAuthorization(
                            address from,
                            address to,
                            uint256 value,
                            uint256 validAfter,
                            uint256 validBefore,
                            bytes32 nonce,
                            bytes memory signature
                        ) external whenNotPaused notBlacklisted(from) notBlacklisted(to) {
                            _transferWithAuthorization(
                                from,
                                to,
                                value,
                                validAfter,
                                validBefore,
                                nonce,
                                signature
                            );
                        }
                        /**
                         * @notice Receive a transfer with a signed authorization from the payer
                         * @dev This has an additional check to ensure that the payee's address
                         * matches the caller of this function to prevent front-running attacks.
                         * EOA wallet signatures should be packed in the order of r, s, v.
                         * @param from          Payer's address (Authorizer)
                         * @param to            Payee's address
                         * @param value         Amount to be transferred
                         * @param validAfter    The time after which this is valid (unix time)
                         * @param validBefore   The time before which this is valid (unix time)
                         * @param nonce         Unique nonce
                         * @param signature     Signature bytes signed by an EOA wallet or a contract wallet
                         */
                        function receiveWithAuthorization(
                            address from,
                            address to,
                            uint256 value,
                            uint256 validAfter,
                            uint256 validBefore,
                            bytes32 nonce,
                            bytes memory signature
                        ) external whenNotPaused notBlacklisted(from) notBlacklisted(to) {
                            _receiveWithAuthorization(
                                from,
                                to,
                                value,
                                validAfter,
                                validBefore,
                                nonce,
                                signature
                            );
                        }
                        /**
                         * @notice Attempt to cancel an authorization
                         * @dev Works only if the authorization is not yet used.
                         * EOA wallet signatures should be packed in the order of r, s, v.
                         * @param authorizer    Authorizer's address
                         * @param nonce         Nonce of the authorization
                         * @param signature     Signature bytes signed by an EOA wallet or a contract wallet
                         */
                        function cancelAuthorization(
                            address authorizer,
                            bytes32 nonce,
                            bytes memory signature
                        ) external whenNotPaused {
                            _cancelAuthorization(authorizer, nonce, signature);
                        }
                        /**
                         * @dev Helper method that sets the blacklist state of an account on balanceAndBlacklistStates.
                         * If _shouldBlacklist is true, we apply a (1 << 255) bitmask with an OR operation on the
                         * account's balanceAndBlacklistState. This flips the high bit for the account to 1,
                         * indicating that the account is blacklisted.
                         *
                         * If _shouldBlacklist if false, we reset the account's balanceAndBlacklistStates to their
                         * balances. This clears the high bit for the account, indicating that the account is unblacklisted.
                         * @param _account         The address of the account.
                         * @param _shouldBlacklist True if the account should be blacklisted, false if the account should be unblacklisted.
                         */
                        function _setBlacklistState(address _account, bool _shouldBlacklist)
                            internal
                            override
                        {
                            balanceAndBlacklistStates[_account] = _shouldBlacklist
                                ? balanceAndBlacklistStates[_account] | (1 << 255)
                                : _balanceOf(_account);
                        }
                        /**
                         * @dev Helper method that sets the balance of an account on balanceAndBlacklistStates.
                         * Since balances are stored in the last 255 bits of the balanceAndBlacklistStates value,
                         * we need to ensure that the updated balance does not exceed (2^255 - 1).
                         * Since blacklisted accounts' balances cannot be updated, the method will also
                         * revert if the account is blacklisted
                         * @param _account The address of the account.
                         * @param _balance The new fiat token balance of the account (max: (2^255 - 1)).
                         */
                        function _setBalance(address _account, uint256 _balance) internal override {
                            require(
                                _balance <= ((1 << 255) - 1),
                                "FiatTokenV2_2: Balance exceeds (2^255 - 1)"
                            );
                            require(
                                !_isBlacklisted(_account),
                                "FiatTokenV2_2: Account is blacklisted"
                            );
                            balanceAndBlacklistStates[_account] = _balance;
                        }
                        /**
                         * @inheritdoc Blacklistable
                         */
                        function _isBlacklisted(address _account)
                            internal
                            override
                            view
                            returns (bool)
                        {
                            return balanceAndBlacklistStates[_account] >> 255 == 1;
                        }
                        /**
                         * @dev Helper method to obtain the balance of an account. Since balances
                         * are stored in the last 255 bits of the balanceAndBlacklistStates value,
                         * we apply a ((1 << 255) - 1) bit bitmask with an AND operation on the
                         * balanceAndBlacklistState to obtain the balance.
                         * @param _account  The address of the account.
                         * @return          The fiat token balance of the account.
                         */
                        function _balanceOf(address _account)
                            internal
                            override
                            view
                            returns (uint256)
                        {
                            return balanceAndBlacklistStates[_account] & ((1 << 255) - 1);
                        }
                        /**
                         * @inheritdoc FiatTokenV1
                         */
                        function approve(address spender, uint256 value)
                            external
                            override
                            whenNotPaused
                            returns (bool)
                        {
                            _approve(msg.sender, spender, value);
                            return true;
                        }
                        /**
                         * @inheritdoc FiatTokenV2
                         */
                        function permit(
                            address owner,
                            address spender,
                            uint256 value,
                            uint256 deadline,
                            uint8 v,
                            bytes32 r,
                            bytes32 s
                        ) external override whenNotPaused {
                            _permit(owner, spender, value, deadline, v, r, s);
                        }
                        /**
                         * @inheritdoc FiatTokenV2
                         */
                        function increaseAllowance(address spender, uint256 increment)
                            external
                            override
                            whenNotPaused
                            returns (bool)
                        {
                            _increaseAllowance(msg.sender, spender, increment);
                            return true;
                        }
                        /**
                         * @inheritdoc FiatTokenV2
                         */
                        function decreaseAllowance(address spender, uint256 decrement)
                            external
                            override
                            whenNotPaused
                            returns (bool)
                        {
                            _decreaseAllowance(msg.sender, spender, decrement);
                            return true;
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    pragma solidity >=0.6.2 <0.8.0;
                    /**
                     * @dev Collection of functions related to the address type
                     */
                    library Address {
                        /**
                         * @dev Returns true if `account` is a contract.
                         *
                         * [IMPORTANT]
                         * ====
                         * It is unsafe to assume that an address for which this function returns
                         * false is an externally-owned account (EOA) and not a contract.
                         *
                         * Among others, `isContract` will return false for the following
                         * types of addresses:
                         *
                         *  - an externally-owned account
                         *  - a contract in construction
                         *  - an address where a contract will be created
                         *  - an address where a contract lived, but was destroyed
                         * ====
                         */
                        function isContract(address account) internal view returns (bool) {
                            // This method relies on extcodesize, which returns 0 for contracts in
                            // construction, since the code is only stored at the end of the
                            // constructor execution.
                            uint256 size;
                            // solhint-disable-next-line no-inline-assembly
                            assembly { size := extcodesize(account) }
                            return size > 0;
                        }
                        /**
                         * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
                         * `recipient`, forwarding all available gas and reverting on errors.
                         *
                         * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
                         * of certain opcodes, possibly making contracts go over the 2300 gas limit
                         * imposed by `transfer`, making them unable to receive funds via
                         * `transfer`. {sendValue} removes this limitation.
                         *
                         * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
                         *
                         * IMPORTANT: because control is transferred to `recipient`, care must be
                         * taken to not create reentrancy vulnerabilities. Consider using
                         * {ReentrancyGuard} or the
                         * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
                         */
                        function sendValue(address payable recipient, uint256 amount) internal {
                            require(address(this).balance >= amount, "Address: insufficient balance");
                            // solhint-disable-next-line avoid-low-level-calls, avoid-call-value
                            (bool success, ) = recipient.call{ value: amount }("");
                            require(success, "Address: unable to send value, recipient may have reverted");
                        }
                        /**
                         * @dev Performs a Solidity function call using a low level `call`. A
                         * plain`call` is an unsafe replacement for a function call: use this
                         * function instead.
                         *
                         * If `target` reverts with a revert reason, it is bubbled up by this
                         * function (like regular Solidity function calls).
                         *
                         * Returns the raw returned data. To convert to the expected return value,
                         * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
                         *
                         * Requirements:
                         *
                         * - `target` must be a contract.
                         * - calling `target` with `data` must not revert.
                         *
                         * _Available since v3.1._
                         */
                        function functionCall(address target, bytes memory data) internal returns (bytes memory) {
                          return functionCall(target, data, "Address: low-level call failed");
                        }
                        /**
                         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
                         * `errorMessage` as a fallback revert reason when `target` reverts.
                         *
                         * _Available since v3.1._
                         */
                        function functionCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {
                            return functionCallWithValue(target, data, 0, errorMessage);
                        }
                        /**
                         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
                         * but also transferring `value` wei to `target`.
                         *
                         * Requirements:
                         *
                         * - the calling contract must have an ETH balance of at least `value`.
                         * - the called Solidity function must be `payable`.
                         *
                         * _Available since v3.1._
                         */
                        function functionCallWithValue(address target, bytes memory data, uint256 value) internal returns (bytes memory) {
                            return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
                        }
                        /**
                         * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
                         * with `errorMessage` as a fallback revert reason when `target` reverts.
                         *
                         * _Available since v3.1._
                         */
                        function functionCallWithValue(address target, bytes memory data, uint256 value, string memory errorMessage) internal returns (bytes memory) {
                            require(address(this).balance >= value, "Address: insufficient balance for call");
                            require(isContract(target), "Address: call to non-contract");
                            // solhint-disable-next-line avoid-low-level-calls
                            (bool success, bytes memory returndata) = target.call{ value: value }(data);
                            return _verifyCallResult(success, returndata, errorMessage);
                        }
                        /**
                         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
                         * but performing a static call.
                         *
                         * _Available since v3.3._
                         */
                        function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
                            return functionStaticCall(target, data, "Address: low-level static call failed");
                        }
                        /**
                         * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
                         * but performing a static call.
                         *
                         * _Available since v3.3._
                         */
                        function functionStaticCall(address target, bytes memory data, string memory errorMessage) internal view returns (bytes memory) {
                            require(isContract(target), "Address: static call to non-contract");
                            // solhint-disable-next-line avoid-low-level-calls
                            (bool success, bytes memory returndata) = target.staticcall(data);
                            return _verifyCallResult(success, returndata, errorMessage);
                        }
                        /**
                         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
                         * but performing a delegate call.
                         *
                         * _Available since v3.4._
                         */
                        function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
                            return functionDelegateCall(target, data, "Address: low-level delegate call failed");
                        }
                        /**
                         * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
                         * but performing a delegate call.
                         *
                         * _Available since v3.4._
                         */
                        function functionDelegateCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {
                            require(isContract(target), "Address: delegate call to non-contract");
                            // solhint-disable-next-line avoid-low-level-calls
                            (bool success, bytes memory returndata) = target.delegatecall(data);
                            return _verifyCallResult(success, returndata, errorMessage);
                        }
                        function _verifyCallResult(bool success, bytes memory returndata, string memory errorMessage) private pure returns(bytes memory) {
                            if (success) {
                                return returndata;
                            } else {
                                // Look for revert reason and bubble it up if present
                                if (returndata.length > 0) {
                                    // The easiest way to bubble the revert reason is using memory via assembly
                                    // solhint-disable-next-line no-inline-assembly
                                    assembly {
                                        let returndata_size := mload(returndata)
                                        revert(add(32, returndata), returndata_size)
                                    }
                                } else {
                                    revert(errorMessage);
                                }
                            }
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    pragma solidity >=0.6.0 <0.8.0;
                    import "./IERC20.sol";
                    import "../../math/SafeMath.sol";
                    import "../../utils/Address.sol";
                    /**
                     * @title SafeERC20
                     * @dev Wrappers around ERC20 operations that throw on failure (when the token
                     * contract returns false). Tokens that return no value (and instead revert or
                     * throw on failure) are also supported, non-reverting calls are assumed to be
                     * successful.
                     * To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract,
                     * which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
                     */
                    library SafeERC20 {
                        using SafeMath for uint256;
                        using Address for address;
                        function safeTransfer(IERC20 token, address to, uint256 value) internal {
                            _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
                        }
                        function safeTransferFrom(IERC20 token, address from, address to, uint256 value) internal {
                            _callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
                        }
                        /**
                         * @dev Deprecated. This function has issues similar to the ones found in
                         * {IERC20-approve}, and its usage is discouraged.
                         *
                         * Whenever possible, use {safeIncreaseAllowance} and
                         * {safeDecreaseAllowance} instead.
                         */
                        function safeApprove(IERC20 token, address spender, uint256 value) internal {
                            // safeApprove should only be called when setting an initial allowance,
                            // or when resetting it to zero. To increase and decrease it, use
                            // 'safeIncreaseAllowance' and 'safeDecreaseAllowance'
                            // solhint-disable-next-line max-line-length
                            require((value == 0) || (token.allowance(address(this), spender) == 0),
                                "SafeERC20: approve from non-zero to non-zero allowance"
                            );
                            _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
                        }
                        function safeIncreaseAllowance(IERC20 token, address spender, uint256 value) internal {
                            uint256 newAllowance = token.allowance(address(this), spender).add(value);
                            _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
                        }
                        function safeDecreaseAllowance(IERC20 token, address spender, uint256 value) internal {
                            uint256 newAllowance = token.allowance(address(this), spender).sub(value, "SafeERC20: decreased allowance below zero");
                            _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
                        }
                        /**
                         * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
                         * on the return value: the return value is optional (but if data is returned, it must not be false).
                         * @param token The token targeted by the call.
                         * @param data The call data (encoded using abi.encode or one of its variants).
                         */
                        function _callOptionalReturn(IERC20 token, bytes memory data) private {
                            // We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
                            // we're implementing it ourselves. We use {Address.functionCall} to perform this call, which verifies that
                            // the target address contains contract code and also asserts for success in the low-level call.
                            bytes memory returndata = address(token).functionCall(data, "SafeERC20: low-level call failed");
                            if (returndata.length > 0) { // Return data is optional
                                // solhint-disable-next-line max-line-length
                                require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
                            }
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    pragma solidity >=0.6.0 <0.8.0;
                    /**
                     * @dev Interface of the ERC20 standard as defined in the EIP.
                     */
                    interface IERC20 {
                        /**
                         * @dev Returns the amount of tokens in existence.
                         */
                        function totalSupply() external view returns (uint256);
                        /**
                         * @dev Returns the amount of tokens owned by `account`.
                         */
                        function balanceOf(address account) external view returns (uint256);
                        /**
                         * @dev Moves `amount` tokens from the caller's account to `recipient`.
                         *
                         * Returns a boolean value indicating whether the operation succeeded.
                         *
                         * Emits a {Transfer} event.
                         */
                        function transfer(address recipient, uint256 amount) external returns (bool);
                        /**
                         * @dev Returns the remaining number of tokens that `spender` will be
                         * allowed to spend on behalf of `owner` through {transferFrom}. This is
                         * zero by default.
                         *
                         * This value changes when {approve} or {transferFrom} are called.
                         */
                        function allowance(address owner, address spender) external view returns (uint256);
                        /**
                         * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
                         *
                         * Returns a boolean value indicating whether the operation succeeded.
                         *
                         * IMPORTANT: Beware that changing an allowance with this method brings the risk
                         * that someone may use both the old and the new allowance by unfortunate
                         * transaction ordering. One possible solution to mitigate this race
                         * condition is to first reduce the spender's allowance to 0 and set the
                         * desired value afterwards:
                         * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
                         *
                         * Emits an {Approval} event.
                         */
                        function approve(address spender, uint256 amount) external returns (bool);
                        /**
                         * @dev Moves `amount` tokens from `sender` to `recipient` using the
                         * allowance mechanism. `amount` is then deducted from the caller's
                         * allowance.
                         *
                         * Returns a boolean value indicating whether the operation succeeded.
                         *
                         * Emits a {Transfer} event.
                         */
                        function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);
                        /**
                         * @dev Emitted when `value` tokens are moved from one account (`from`) to
                         * another (`to`).
                         *
                         * Note that `value` may be zero.
                         */
                        event Transfer(address indexed from, address indexed to, uint256 value);
                        /**
                         * @dev Emitted when the allowance of a `spender` for an `owner` is set by
                         * a call to {approve}. `value` is the new allowance.
                         */
                        event Approval(address indexed owner, address indexed spender, uint256 value);
                    }
                    // SPDX-License-Identifier: MIT
                    pragma solidity >=0.6.0 <0.8.0;
                    /**
                     * @dev Wrappers over Solidity's arithmetic operations with added overflow
                     * checks.
                     *
                     * Arithmetic operations in Solidity wrap on overflow. This can easily result
                     * in bugs, because programmers usually assume that an overflow raises an
                     * error, which is the standard behavior in high level programming languages.
                     * `SafeMath` restores this intuition by reverting the transaction when an
                     * operation overflows.
                     *
                     * Using this library instead of the unchecked operations eliminates an entire
                     * class of bugs, so it's recommended to use it always.
                     */
                    library SafeMath {
                        /**
                         * @dev Returns the addition of two unsigned integers, with an overflow flag.
                         *
                         * _Available since v3.4._
                         */
                        function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
                            uint256 c = a + b;
                            if (c < a) return (false, 0);
                            return (true, c);
                        }
                        /**
                         * @dev Returns the substraction of two unsigned integers, with an overflow flag.
                         *
                         * _Available since v3.4._
                         */
                        function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
                            if (b > a) return (false, 0);
                            return (true, a - b);
                        }
                        /**
                         * @dev Returns the multiplication of two unsigned integers, with an overflow flag.
                         *
                         * _Available since v3.4._
                         */
                        function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
                            // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
                            // benefit is lost if 'b' is also tested.
                            // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
                            if (a == 0) return (true, 0);
                            uint256 c = a * b;
                            if (c / a != b) return (false, 0);
                            return (true, c);
                        }
                        /**
                         * @dev Returns the division of two unsigned integers, with a division by zero flag.
                         *
                         * _Available since v3.4._
                         */
                        function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
                            if (b == 0) return (false, 0);
                            return (true, a / b);
                        }
                        /**
                         * @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.
                         *
                         * _Available since v3.4._
                         */
                        function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
                            if (b == 0) return (false, 0);
                            return (true, a % b);
                        }
                        /**
                         * @dev Returns the addition of two unsigned integers, reverting on
                         * overflow.
                         *
                         * Counterpart to Solidity's `+` operator.
                         *
                         * Requirements:
                         *
                         * - Addition cannot overflow.
                         */
                        function add(uint256 a, uint256 b) internal pure returns (uint256) {
                            uint256 c = a + b;
                            require(c >= a, "SafeMath: addition overflow");
                            return c;
                        }
                        /**
                         * @dev Returns the subtraction of two unsigned integers, reverting on
                         * overflow (when the result is negative).
                         *
                         * Counterpart to Solidity's `-` operator.
                         *
                         * Requirements:
                         *
                         * - Subtraction cannot overflow.
                         */
                        function sub(uint256 a, uint256 b) internal pure returns (uint256) {
                            require(b <= a, "SafeMath: subtraction overflow");
                            return a - b;
                        }
                        /**
                         * @dev Returns the multiplication of two unsigned integers, reverting on
                         * overflow.
                         *
                         * Counterpart to Solidity's `*` operator.
                         *
                         * Requirements:
                         *
                         * - Multiplication cannot overflow.
                         */
                        function mul(uint256 a, uint256 b) internal pure returns (uint256) {
                            if (a == 0) return 0;
                            uint256 c = a * b;
                            require(c / a == b, "SafeMath: multiplication overflow");
                            return c;
                        }
                        /**
                         * @dev Returns the integer division of two unsigned integers, reverting on
                         * division by zero. The result is rounded towards zero.
                         *
                         * Counterpart to Solidity's `/` operator. Note: this function uses a
                         * `revert` opcode (which leaves remaining gas untouched) while Solidity
                         * uses an invalid opcode to revert (consuming all remaining gas).
                         *
                         * Requirements:
                         *
                         * - The divisor cannot be zero.
                         */
                        function div(uint256 a, uint256 b) internal pure returns (uint256) {
                            require(b > 0, "SafeMath: division by zero");
                            return a / b;
                        }
                        /**
                         * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
                         * reverting when dividing by zero.
                         *
                         * Counterpart to Solidity's `%` operator. This function uses a `revert`
                         * opcode (which leaves remaining gas untouched) while Solidity uses an
                         * invalid opcode to revert (consuming all remaining gas).
                         *
                         * Requirements:
                         *
                         * - The divisor cannot be zero.
                         */
                        function mod(uint256 a, uint256 b) internal pure returns (uint256) {
                            require(b > 0, "SafeMath: modulo by zero");
                            return a % b;
                        }
                        /**
                         * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
                         * overflow (when the result is negative).
                         *
                         * CAUTION: This function is deprecated because it requires allocating memory for the error
                         * message unnecessarily. For custom revert reasons use {trySub}.
                         *
                         * Counterpart to Solidity's `-` operator.
                         *
                         * Requirements:
                         *
                         * - Subtraction cannot overflow.
                         */
                        function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
                            require(b <= a, errorMessage);
                            return a - b;
                        }
                        /**
                         * @dev Returns the integer division of two unsigned integers, reverting with custom message on
                         * division by zero. The result is rounded towards zero.
                         *
                         * CAUTION: This function is deprecated because it requires allocating memory for the error
                         * message unnecessarily. For custom revert reasons use {tryDiv}.
                         *
                         * Counterpart to Solidity's `/` operator. Note: this function uses a
                         * `revert` opcode (which leaves remaining gas untouched) while Solidity
                         * uses an invalid opcode to revert (consuming all remaining gas).
                         *
                         * Requirements:
                         *
                         * - The divisor cannot be zero.
                         */
                        function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
                            require(b > 0, errorMessage);
                            return a / b;
                        }
                        /**
                         * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
                         * reverting with custom message when dividing by zero.
                         *
                         * CAUTION: This function is deprecated because it requires allocating memory for the error
                         * message unnecessarily. For custom revert reasons use {tryMod}.
                         *
                         * Counterpart to Solidity's `%` operator. This function uses a `revert`
                         * opcode (which leaves remaining gas untouched) while Solidity uses an
                         * invalid opcode to revert (consuming all remaining gas).
                         *
                         * Requirements:
                         *
                         * - The divisor cannot be zero.
                         */
                        function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
                            require(b > 0, errorMessage);
                            return a % b;
                        }
                    }
                    /**
                     * SPDX-License-Identifier: Apache-2.0
                     *
                     * Copyright (c) 2023, Circle Internet Financial, LLC.
                     *
                     * Licensed under the Apache License, Version 2.0 (the "License");
                     * you may not use this file except in compliance with the License.
                     * You may obtain a copy of the License at
                     *
                     * http://www.apache.org/licenses/LICENSE-2.0
                     *
                     * Unless required by applicable law or agreed to in writing, software
                     * distributed under the License is distributed on an "AS IS" BASIS,
                     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
                     * See the License for the specific language governing permissions and
                     * limitations under the License.
                     */
                    pragma solidity 0.6.12;
                    import { FiatTokenV2 } from "./FiatTokenV2.sol";
                    // solhint-disable func-name-mixedcase
                    /**
                     * @title FiatToken V2.1
                     * @notice ERC20 Token backed by fiat reserves, version 2.1
                     */
                    contract FiatTokenV2_1 is FiatTokenV2 {
                        /**
                         * @notice Initialize v2.1
                         * @param lostAndFound  The address to which the locked funds are sent
                         */
                        function initializeV2_1(address lostAndFound) external {
                            // solhint-disable-next-line reason-string
                            require(_initializedVersion == 1);
                            uint256 lockedAmount = _balanceOf(address(this));
                            if (lockedAmount > 0) {
                                _transfer(address(this), lostAndFound, lockedAmount);
                            }
                            _blacklist(address(this));
                            _initializedVersion = 2;
                        }
                        /**
                         * @notice Version string for the EIP712 domain separator
                         * @return Version string
                         */
                        function version() external pure returns (string memory) {
                            return "2";
                        }
                    }
                    /**
                     * SPDX-License-Identifier: Apache-2.0
                     *
                     * Copyright (c) 2023, Circle Internet Financial, LLC.
                     *
                     * Licensed under the Apache License, Version 2.0 (the "License");
                     * you may not use this file except in compliance with the License.
                     * You may obtain a copy of the License at
                     *
                     * http://www.apache.org/licenses/LICENSE-2.0
                     *
                     * Unless required by applicable law or agreed to in writing, software
                     * distributed under the License is distributed on an "AS IS" BASIS,
                     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
                     * See the License for the specific language governing permissions and
                     * limitations under the License.
                     */
                    pragma solidity 0.6.12;
                    import { FiatTokenV1_1 } from "../v1.1/FiatTokenV1_1.sol";
                    import { EIP712 } from "../util/EIP712.sol";
                    import { EIP3009 } from "./EIP3009.sol";
                    import { EIP2612 } from "./EIP2612.sol";
                    /**
                     * @title FiatToken V2
                     * @notice ERC20 Token backed by fiat reserves, version 2
                     */
                    contract FiatTokenV2 is FiatTokenV1_1, EIP3009, EIP2612 {
                        uint8 internal _initializedVersion;
                        /**
                         * @notice Initialize v2
                         * @param newName   New token name
                         */
                        function initializeV2(string calldata newName) external {
                            // solhint-disable-next-line reason-string
                            require(initialized && _initializedVersion == 0);
                            name = newName;
                            _DEPRECATED_CACHED_DOMAIN_SEPARATOR = EIP712.makeDomainSeparator(
                                newName,
                                "2"
                            );
                            _initializedVersion = 1;
                        }
                        /**
                         * @notice Increase the allowance by a given increment
                         * @param spender   Spender's address
                         * @param increment Amount of increase in allowance
                         * @return True if successful
                         */
                        function increaseAllowance(address spender, uint256 increment)
                            external
                            virtual
                            whenNotPaused
                            notBlacklisted(msg.sender)
                            notBlacklisted(spender)
                            returns (bool)
                        {
                            _increaseAllowance(msg.sender, spender, increment);
                            return true;
                        }
                        /**
                         * @notice Decrease the allowance by a given decrement
                         * @param spender   Spender's address
                         * @param decrement Amount of decrease in allowance
                         * @return True if successful
                         */
                        function decreaseAllowance(address spender, uint256 decrement)
                            external
                            virtual
                            whenNotPaused
                            notBlacklisted(msg.sender)
                            notBlacklisted(spender)
                            returns (bool)
                        {
                            _decreaseAllowance(msg.sender, spender, decrement);
                            return true;
                        }
                        /**
                         * @notice Execute a transfer with a signed authorization
                         * @param from          Payer's address (Authorizer)
                         * @param to            Payee's address
                         * @param value         Amount to be transferred
                         * @param validAfter    The time after which this is valid (unix time)
                         * @param validBefore   The time before which this is valid (unix time)
                         * @param nonce         Unique nonce
                         * @param v             v of the signature
                         * @param r             r of the signature
                         * @param s             s of the signature
                         */
                        function transferWithAuthorization(
                            address from,
                            address to,
                            uint256 value,
                            uint256 validAfter,
                            uint256 validBefore,
                            bytes32 nonce,
                            uint8 v,
                            bytes32 r,
                            bytes32 s
                        ) external whenNotPaused notBlacklisted(from) notBlacklisted(to) {
                            _transferWithAuthorization(
                                from,
                                to,
                                value,
                                validAfter,
                                validBefore,
                                nonce,
                                v,
                                r,
                                s
                            );
                        }
                        /**
                         * @notice Receive a transfer with a signed authorization from the payer
                         * @dev This has an additional check to ensure that the payee's address
                         * matches the caller of this function to prevent front-running attacks.
                         * @param from          Payer's address (Authorizer)
                         * @param to            Payee's address
                         * @param value         Amount to be transferred
                         * @param validAfter    The time after which this is valid (unix time)
                         * @param validBefore   The time before which this is valid (unix time)
                         * @param nonce         Unique nonce
                         * @param v             v of the signature
                         * @param r             r of the signature
                         * @param s             s of the signature
                         */
                        function receiveWithAuthorization(
                            address from,
                            address to,
                            uint256 value,
                            uint256 validAfter,
                            uint256 validBefore,
                            bytes32 nonce,
                            uint8 v,
                            bytes32 r,
                            bytes32 s
                        ) external whenNotPaused notBlacklisted(from) notBlacklisted(to) {
                            _receiveWithAuthorization(
                                from,
                                to,
                                value,
                                validAfter,
                                validBefore,
                                nonce,
                                v,
                                r,
                                s
                            );
                        }
                        /**
                         * @notice Attempt to cancel an authorization
                         * @dev Works only if the authorization is not yet used.
                         * @param authorizer    Authorizer's address
                         * @param nonce         Nonce of the authorization
                         * @param v             v of the signature
                         * @param r             r of the signature
                         * @param s             s of the signature
                         */
                        function cancelAuthorization(
                            address authorizer,
                            bytes32 nonce,
                            uint8 v,
                            bytes32 r,
                            bytes32 s
                        ) external whenNotPaused {
                            _cancelAuthorization(authorizer, nonce, v, r, s);
                        }
                        /**
                         * @notice Update allowance with a signed permit
                         * @param owner       Token owner's address (Authorizer)
                         * @param spender     Spender's address
                         * @param value       Amount of allowance
                         * @param deadline    The time at which the signature expires (unix time), or max uint256 value to signal no expiration
                         * @param v           v of the signature
                         * @param r           r of the signature
                         * @param s           s of the signature
                         */
                        function permit(
                            address owner,
                            address spender,
                            uint256 value,
                            uint256 deadline,
                            uint8 v,
                            bytes32 r,
                            bytes32 s
                        )
                            external
                            virtual
                            whenNotPaused
                            notBlacklisted(owner)
                            notBlacklisted(spender)
                        {
                            _permit(owner, spender, value, deadline, v, r, s);
                        }
                        /**
                         * @dev Internal function to increase the allowance by a given increment
                         * @param owner     Token owner's address
                         * @param spender   Spender's address
                         * @param increment Amount of increase
                         */
                        function _increaseAllowance(
                            address owner,
                            address spender,
                            uint256 increment
                        ) internal override {
                            _approve(owner, spender, allowed[owner][spender].add(increment));
                        }
                        /**
                         * @dev Internal function to decrease the allowance by a given decrement
                         * @param owner     Token owner's address
                         * @param spender   Spender's address
                         * @param decrement Amount of decrease
                         */
                        function _decreaseAllowance(
                            address owner,
                            address spender,
                            uint256 decrement
                        ) internal override {
                            _approve(
                                owner,
                                spender,
                                allowed[owner][spender].sub(
                                    decrement,
                                    "ERC20: decreased allowance below zero"
                                )
                            );
                        }
                    }
                    /**
                     * SPDX-License-Identifier: Apache-2.0
                     *
                     * Copyright (c) 2023, Circle Internet Financial, LLC.
                     *
                     * Licensed under the Apache License, Version 2.0 (the "License");
                     * you may not use this file except in compliance with the License.
                     * You may obtain a copy of the License at
                     *
                     * http://www.apache.org/licenses/LICENSE-2.0
                     *
                     * Unless required by applicable law or agreed to in writing, software
                     * distributed under the License is distributed on an "AS IS" BASIS,
                     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
                     * See the License for the specific language governing permissions and
                     * limitations under the License.
                     */
                    pragma solidity 0.6.12;
                    // solhint-disable func-name-mixedcase
                    /**
                     * @title EIP712 Domain
                     */
                    contract EIP712Domain {
                        // was originally DOMAIN_SEPARATOR
                        // but that has been moved to a method so we can override it in V2_2+
                        bytes32 internal _DEPRECATED_CACHED_DOMAIN_SEPARATOR;
                        /**
                         * @notice Get the EIP712 Domain Separator.
                         * @return The bytes32 EIP712 domain separator.
                         */
                        function DOMAIN_SEPARATOR() external view returns (bytes32) {
                            return _domainSeparator();
                        }
                        /**
                         * @dev Internal method to get the EIP712 Domain Separator.
                         * @return The bytes32 EIP712 domain separator.
                         */
                        function _domainSeparator() internal virtual view returns (bytes32) {
                            return _DEPRECATED_CACHED_DOMAIN_SEPARATOR;
                        }
                    }
                    /**
                     * SPDX-License-Identifier: Apache-2.0
                     *
                     * Copyright (c) 2023, Circle Internet Financial, LLC.
                     *
                     * Licensed under the Apache License, Version 2.0 (the "License");
                     * you may not use this file except in compliance with the License.
                     * You may obtain a copy of the License at
                     *
                     * http://www.apache.org/licenses/LICENSE-2.0
                     *
                     * Unless required by applicable law or agreed to in writing, software
                     * distributed under the License is distributed on an "AS IS" BASIS,
                     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
                     * See the License for the specific language governing permissions and
                     * limitations under the License.
                     */
                    pragma solidity 0.6.12;
                    import { AbstractFiatTokenV2 } from "./AbstractFiatTokenV2.sol";
                    import { EIP712Domain } from "./EIP712Domain.sol";
                    import { SignatureChecker } from "../util/SignatureChecker.sol";
                    import { MessageHashUtils } from "../util/MessageHashUtils.sol";
                    /**
                     * @title EIP-3009
                     * @notice Provide internal implementation for gas-abstracted transfers
                     * @dev Contracts that inherit from this must wrap these with publicly
                     * accessible functions, optionally adding modifiers where necessary
                     */
                    abstract contract EIP3009 is AbstractFiatTokenV2, EIP712Domain {
                        // keccak256("TransferWithAuthorization(address from,address to,uint256 value,uint256 validAfter,uint256 validBefore,bytes32 nonce)")
                        bytes32
                            public constant TRANSFER_WITH_AUTHORIZATION_TYPEHASH = 0x7c7c6cdb67a18743f49ec6fa9b35f50d52ed05cbed4cc592e13b44501c1a2267;
                        // keccak256("ReceiveWithAuthorization(address from,address to,uint256 value,uint256 validAfter,uint256 validBefore,bytes32 nonce)")
                        bytes32
                            public constant RECEIVE_WITH_AUTHORIZATION_TYPEHASH = 0xd099cc98ef71107a616c4f0f941f04c322d8e254fe26b3c6668db87aae413de8;
                        // keccak256("CancelAuthorization(address authorizer,bytes32 nonce)")
                        bytes32
                            public constant CANCEL_AUTHORIZATION_TYPEHASH = 0x158b0a9edf7a828aad02f63cd515c68ef2f50ba807396f6d12842833a1597429;
                        /**
                         * @dev authorizer address => nonce => bool (true if nonce is used)
                         */
                        mapping(address => mapping(bytes32 => bool)) private _authorizationStates;
                        event AuthorizationUsed(address indexed authorizer, bytes32 indexed nonce);
                        event AuthorizationCanceled(
                            address indexed authorizer,
                            bytes32 indexed nonce
                        );
                        /**
                         * @notice Returns the state of an authorization
                         * @dev Nonces are randomly generated 32-byte data unique to the
                         * authorizer's address
                         * @param authorizer    Authorizer's address
                         * @param nonce         Nonce of the authorization
                         * @return True if the nonce is used
                         */
                        function authorizationState(address authorizer, bytes32 nonce)
                            external
                            view
                            returns (bool)
                        {
                            return _authorizationStates[authorizer][nonce];
                        }
                        /**
                         * @notice Execute a transfer with a signed authorization
                         * @param from          Payer's address (Authorizer)
                         * @param to            Payee's address
                         * @param value         Amount to be transferred
                         * @param validAfter    The time after which this is valid (unix time)
                         * @param validBefore   The time before which this is valid (unix time)
                         * @param nonce         Unique nonce
                         * @param v             v of the signature
                         * @param r             r of the signature
                         * @param s             s of the signature
                         */
                        function _transferWithAuthorization(
                            address from,
                            address to,
                            uint256 value,
                            uint256 validAfter,
                            uint256 validBefore,
                            bytes32 nonce,
                            uint8 v,
                            bytes32 r,
                            bytes32 s
                        ) internal {
                            _transferWithAuthorization(
                                from,
                                to,
                                value,
                                validAfter,
                                validBefore,
                                nonce,
                                abi.encodePacked(r, s, v)
                            );
                        }
                        /**
                         * @notice Execute a transfer with a signed authorization
                         * @dev EOA wallet signatures should be packed in the order of r, s, v.
                         * @param from          Payer's address (Authorizer)
                         * @param to            Payee's address
                         * @param value         Amount to be transferred
                         * @param validAfter    The time after which this is valid (unix time)
                         * @param validBefore   The time before which this is valid (unix time)
                         * @param nonce         Unique nonce
                         * @param signature     Signature byte array produced by an EOA wallet or a contract wallet
                         */
                        function _transferWithAuthorization(
                            address from,
                            address to,
                            uint256 value,
                            uint256 validAfter,
                            uint256 validBefore,
                            bytes32 nonce,
                            bytes memory signature
                        ) internal {
                            _requireValidAuthorization(from, nonce, validAfter, validBefore);
                            _requireValidSignature(
                                from,
                                keccak256(
                                    abi.encode(
                                        TRANSFER_WITH_AUTHORIZATION_TYPEHASH,
                                        from,
                                        to,
                                        value,
                                        validAfter,
                                        validBefore,
                                        nonce
                                    )
                                ),
                                signature
                            );
                            _markAuthorizationAsUsed(from, nonce);
                            _transfer(from, to, value);
                        }
                        /**
                         * @notice Receive a transfer with a signed authorization from the payer
                         * @dev This has an additional check to ensure that the payee's address
                         * matches the caller of this function to prevent front-running attacks.
                         * @param from          Payer's address (Authorizer)
                         * @param to            Payee's address
                         * @param value         Amount to be transferred
                         * @param validAfter    The time after which this is valid (unix time)
                         * @param validBefore   The time before which this is valid (unix time)
                         * @param nonce         Unique nonce
                         * @param v             v of the signature
                         * @param r             r of the signature
                         * @param s             s of the signature
                         */
                        function _receiveWithAuthorization(
                            address from,
                            address to,
                            uint256 value,
                            uint256 validAfter,
                            uint256 validBefore,
                            bytes32 nonce,
                            uint8 v,
                            bytes32 r,
                            bytes32 s
                        ) internal {
                            _receiveWithAuthorization(
                                from,
                                to,
                                value,
                                validAfter,
                                validBefore,
                                nonce,
                                abi.encodePacked(r, s, v)
                            );
                        }
                        /**
                         * @notice Receive a transfer with a signed authorization from the payer
                         * @dev This has an additional check to ensure that the payee's address
                         * matches the caller of this function to prevent front-running attacks.
                         * EOA wallet signatures should be packed in the order of r, s, v.
                         * @param from          Payer's address (Authorizer)
                         * @param to            Payee's address
                         * @param value         Amount to be transferred
                         * @param validAfter    The time after which this is valid (unix time)
                         * @param validBefore   The time before which this is valid (unix time)
                         * @param nonce         Unique nonce
                         * @param signature     Signature byte array produced by an EOA wallet or a contract wallet
                         */
                        function _receiveWithAuthorization(
                            address from,
                            address to,
                            uint256 value,
                            uint256 validAfter,
                            uint256 validBefore,
                            bytes32 nonce,
                            bytes memory signature
                        ) internal {
                            require(to == msg.sender, "FiatTokenV2: caller must be the payee");
                            _requireValidAuthorization(from, nonce, validAfter, validBefore);
                            _requireValidSignature(
                                from,
                                keccak256(
                                    abi.encode(
                                        RECEIVE_WITH_AUTHORIZATION_TYPEHASH,
                                        from,
                                        to,
                                        value,
                                        validAfter,
                                        validBefore,
                                        nonce
                                    )
                                ),
                                signature
                            );
                            _markAuthorizationAsUsed(from, nonce);
                            _transfer(from, to, value);
                        }
                        /**
                         * @notice Attempt to cancel an authorization
                         * @param authorizer    Authorizer's address
                         * @param nonce         Nonce of the authorization
                         * @param v             v of the signature
                         * @param r             r of the signature
                         * @param s             s of the signature
                         */
                        function _cancelAuthorization(
                            address authorizer,
                            bytes32 nonce,
                            uint8 v,
                            bytes32 r,
                            bytes32 s
                        ) internal {
                            _cancelAuthorization(authorizer, nonce, abi.encodePacked(r, s, v));
                        }
                        /**
                         * @notice Attempt to cancel an authorization
                         * @dev EOA wallet signatures should be packed in the order of r, s, v.
                         * @param authorizer    Authorizer's address
                         * @param nonce         Nonce of the authorization
                         * @param signature     Signature byte array produced by an EOA wallet or a contract wallet
                         */
                        function _cancelAuthorization(
                            address authorizer,
                            bytes32 nonce,
                            bytes memory signature
                        ) internal {
                            _requireUnusedAuthorization(authorizer, nonce);
                            _requireValidSignature(
                                authorizer,
                                keccak256(
                                    abi.encode(CANCEL_AUTHORIZATION_TYPEHASH, authorizer, nonce)
                                ),
                                signature
                            );
                            _authorizationStates[authorizer][nonce] = true;
                            emit AuthorizationCanceled(authorizer, nonce);
                        }
                        /**
                         * @notice Validates that signature against input data struct
                         * @param signer        Signer's address
                         * @param dataHash      Hash of encoded data struct
                         * @param signature     Signature byte array produced by an EOA wallet or a contract wallet
                         */
                        function _requireValidSignature(
                            address signer,
                            bytes32 dataHash,
                            bytes memory signature
                        ) private view {
                            require(
                                SignatureChecker.isValidSignatureNow(
                                    signer,
                                    MessageHashUtils.toTypedDataHash(_domainSeparator(), dataHash),
                                    signature
                                ),
                                "FiatTokenV2: invalid signature"
                            );
                        }
                        /**
                         * @notice Check that an authorization is unused
                         * @param authorizer    Authorizer's address
                         * @param nonce         Nonce of the authorization
                         */
                        function _requireUnusedAuthorization(address authorizer, bytes32 nonce)
                            private
                            view
                        {
                            require(
                                !_authorizationStates[authorizer][nonce],
                                "FiatTokenV2: authorization is used or canceled"
                            );
                        }
                        /**
                         * @notice Check that authorization is valid
                         * @param authorizer    Authorizer's address
                         * @param nonce         Nonce of the authorization
                         * @param validAfter    The time after which this is valid (unix time)
                         * @param validBefore   The time before which this is valid (unix time)
                         */
                        function _requireValidAuthorization(
                            address authorizer,
                            bytes32 nonce,
                            uint256 validAfter,
                            uint256 validBefore
                        ) private view {
                            require(
                                now > validAfter,
                                "FiatTokenV2: authorization is not yet valid"
                            );
                            require(now < validBefore, "FiatTokenV2: authorization is expired");
                            _requireUnusedAuthorization(authorizer, nonce);
                        }
                        /**
                         * @notice Mark an authorization as used
                         * @param authorizer    Authorizer's address
                         * @param nonce         Nonce of the authorization
                         */
                        function _markAuthorizationAsUsed(address authorizer, bytes32 nonce)
                            private
                        {
                            _authorizationStates[authorizer][nonce] = true;
                            emit AuthorizationUsed(authorizer, nonce);
                        }
                    }
                    /**
                     * SPDX-License-Identifier: Apache-2.0
                     *
                     * Copyright (c) 2023, Circle Internet Financial, LLC.
                     *
                     * Licensed under the Apache License, Version 2.0 (the "License");
                     * you may not use this file except in compliance with the License.
                     * You may obtain a copy of the License at
                     *
                     * http://www.apache.org/licenses/LICENSE-2.0
                     *
                     * Unless required by applicable law or agreed to in writing, software
                     * distributed under the License is distributed on an "AS IS" BASIS,
                     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
                     * See the License for the specific language governing permissions and
                     * limitations under the License.
                     */
                    pragma solidity 0.6.12;
                    import { AbstractFiatTokenV2 } from "./AbstractFiatTokenV2.sol";
                    import { EIP712Domain } from "./EIP712Domain.sol";
                    import { MessageHashUtils } from "../util/MessageHashUtils.sol";
                    import { SignatureChecker } from "../util/SignatureChecker.sol";
                    /**
                     * @title EIP-2612
                     * @notice Provide internal implementation for gas-abstracted approvals
                     */
                    abstract contract EIP2612 is AbstractFiatTokenV2, EIP712Domain {
                        // keccak256("Permit(address owner,address spender,uint256 value,uint256 nonce,uint256 deadline)")
                        bytes32
                            public constant PERMIT_TYPEHASH = 0x6e71edae12b1b97f4d1f60370fef10105fa2faae0126114a169c64845d6126c9;
                        mapping(address => uint256) private _permitNonces;
                        /**
                         * @notice Nonces for permit
                         * @param owner Token owner's address (Authorizer)
                         * @return Next nonce
                         */
                        function nonces(address owner) external view returns (uint256) {
                            return _permitNonces[owner];
                        }
                        /**
                         * @notice Verify a signed approval permit and execute if valid
                         * @param owner     Token owner's address (Authorizer)
                         * @param spender   Spender's address
                         * @param value     Amount of allowance
                         * @param deadline  The time at which the signature expires (unix time), or max uint256 value to signal no expiration
                         * @param v         v of the signature
                         * @param r         r of the signature
                         * @param s         s of the signature
                         */
                        function _permit(
                            address owner,
                            address spender,
                            uint256 value,
                            uint256 deadline,
                            uint8 v,
                            bytes32 r,
                            bytes32 s
                        ) internal {
                            _permit(owner, spender, value, deadline, abi.encodePacked(r, s, v));
                        }
                        /**
                         * @notice Verify a signed approval permit and execute if valid
                         * @dev EOA wallet signatures should be packed in the order of r, s, v.
                         * @param owner      Token owner's address (Authorizer)
                         * @param spender    Spender's address
                         * @param value      Amount of allowance
                         * @param deadline   The time at which the signature expires (unix time), or max uint256 value to signal no expiration
                         * @param signature  Signature byte array signed by an EOA wallet or a contract wallet
                         */
                        function _permit(
                            address owner,
                            address spender,
                            uint256 value,
                            uint256 deadline,
                            bytes memory signature
                        ) internal {
                            require(
                                deadline == type(uint256).max || deadline >= now,
                                "FiatTokenV2: permit is expired"
                            );
                            bytes32 typedDataHash = MessageHashUtils.toTypedDataHash(
                                _domainSeparator(),
                                keccak256(
                                    abi.encode(
                                        PERMIT_TYPEHASH,
                                        owner,
                                        spender,
                                        value,
                                        _permitNonces[owner]++,
                                        deadline
                                    )
                                )
                            );
                            require(
                                SignatureChecker.isValidSignatureNow(
                                    owner,
                                    typedDataHash,
                                    signature
                                ),
                                "EIP2612: invalid signature"
                            );
                            _approve(owner, spender, value);
                        }
                    }
                    /**
                     * SPDX-License-Identifier: Apache-2.0
                     *
                     * Copyright (c) 2023, Circle Internet Financial, LLC.
                     *
                     * Licensed under the Apache License, Version 2.0 (the "License");
                     * you may not use this file except in compliance with the License.
                     * You may obtain a copy of the License at
                     *
                     * http://www.apache.org/licenses/LICENSE-2.0
                     *
                     * Unless required by applicable law or agreed to in writing, software
                     * distributed under the License is distributed on an "AS IS" BASIS,
                     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
                     * See the License for the specific language governing permissions and
                     * limitations under the License.
                     */
                    pragma solidity 0.6.12;
                    import { AbstractFiatTokenV1 } from "../v1/AbstractFiatTokenV1.sol";
                    abstract contract AbstractFiatTokenV2 is AbstractFiatTokenV1 {
                        function _increaseAllowance(
                            address owner,
                            address spender,
                            uint256 increment
                        ) internal virtual;
                        function _decreaseAllowance(
                            address owner,
                            address spender,
                            uint256 decrement
                        ) internal virtual;
                    }
                    /**
                     * SPDX-License-Identifier: MIT
                     *
                     * Copyright (c) 2016 Smart Contract Solutions, Inc.
                     * Copyright (c) 2018-2020 CENTRE SECZ
                     *
                     * Permission is hereby granted, free of charge, to any person obtaining a copy
                     * of this software and associated documentation files (the "Software"), to deal
                     * in the Software without restriction, including without limitation the rights
                     * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
                     * copies of the Software, and to permit persons to whom the Software is
                     * furnished to do so, subject to the following conditions:
                     *
                     * The above copyright notice and this permission notice shall be included in
                     * copies or substantial portions of the Software.
                     *
                     * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
                     * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
                     * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
                     * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
                     * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
                     * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
                     * SOFTWARE.
                     */
                    pragma solidity 0.6.12;
                    import { Ownable } from "./Ownable.sol";
                    /**
                     * @notice Base contract which allows children to implement an emergency stop
                     * mechanism
                     * @dev Forked from https://github.com/OpenZeppelin/openzeppelin-contracts/blob/feb665136c0dae9912e08397c1a21c4af3651ef3/contracts/lifecycle/Pausable.sol
                     * Modifications:
                     * 1. Added pauser role, switched pause/unpause to be onlyPauser (6/14/2018)
                     * 2. Removed whenNotPause/whenPaused from pause/unpause (6/14/2018)
                     * 3. Removed whenPaused (6/14/2018)
                     * 4. Switches ownable library to use ZeppelinOS (7/12/18)
                     * 5. Remove constructor (7/13/18)
                     * 6. Reformat, conform to Solidity 0.6 syntax and add error messages (5/13/20)
                     * 7. Make public functions external (5/27/20)
                     */
                    contract Pausable is Ownable {
                        event Pause();
                        event Unpause();
                        event PauserChanged(address indexed newAddress);
                        address public pauser;
                        bool public paused = false;
                        /**
                         * @dev Modifier to make a function callable only when the contract is not paused.
                         */
                        modifier whenNotPaused() {
                            require(!paused, "Pausable: paused");
                            _;
                        }
                        /**
                         * @dev throws if called by any account other than the pauser
                         */
                        modifier onlyPauser() {
                            require(msg.sender == pauser, "Pausable: caller is not the pauser");
                            _;
                        }
                        /**
                         * @dev called by the owner to pause, triggers stopped state
                         */
                        function pause() external onlyPauser {
                            paused = true;
                            emit Pause();
                        }
                        /**
                         * @dev called by the owner to unpause, returns to normal state
                         */
                        function unpause() external onlyPauser {
                            paused = false;
                            emit Unpause();
                        }
                        /**
                         * @notice Updates the pauser address.
                         * @param _newPauser The address of the new pauser.
                         */
                        function updatePauser(address _newPauser) external onlyOwner {
                            require(
                                _newPauser != address(0),
                                "Pausable: new pauser is the zero address"
                            );
                            pauser = _newPauser;
                            emit PauserChanged(pauser);
                        }
                    }
                    /**
                     * SPDX-License-Identifier: MIT
                     *
                     * Copyright (c) 2018 zOS Global Limited.
                     * Copyright (c) 2018-2020 CENTRE SECZ
                     *
                     * Permission is hereby granted, free of charge, to any person obtaining a copy
                     * of this software and associated documentation files (the "Software"), to deal
                     * in the Software without restriction, including without limitation the rights
                     * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
                     * copies of the Software, and to permit persons to whom the Software is
                     * furnished to do so, subject to the following conditions:
                     *
                     * The above copyright notice and this permission notice shall be included in
                     * copies or substantial portions of the Software.
                     *
                     * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
                     * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
                     * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
                     * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
                     * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
                     * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
                     * SOFTWARE.
                     */
                    pragma solidity 0.6.12;
                    /**
                     * @notice The Ownable contract has an owner address, and provides basic
                     * authorization control functions
                     * @dev Forked from https://github.com/OpenZeppelin/openzeppelin-labs/blob/3887ab77b8adafba4a26ace002f3a684c1a3388b/upgradeability_ownership/contracts/ownership/Ownable.sol
                     * Modifications:
                     * 1. Consolidate OwnableStorage into this contract (7/13/18)
                     * 2. Reformat, conform to Solidity 0.6 syntax, and add error messages (5/13/20)
                     * 3. Make public functions external (5/27/20)
                     */
                    contract Ownable {
                        // Owner of the contract
                        address private _owner;
                        /**
                         * @dev Event to show ownership has been transferred
                         * @param previousOwner representing the address of the previous owner
                         * @param newOwner representing the address of the new owner
                         */
                        event OwnershipTransferred(address previousOwner, address newOwner);
                        /**
                         * @dev The constructor sets the original owner of the contract to the sender account.
                         */
                        constructor() public {
                            setOwner(msg.sender);
                        }
                        /**
                         * @dev Tells the address of the owner
                         * @return the address of the owner
                         */
                        function owner() external view returns (address) {
                            return _owner;
                        }
                        /**
                         * @dev Sets a new owner address
                         */
                        function setOwner(address newOwner) internal {
                            _owner = newOwner;
                        }
                        /**
                         * @dev Throws if called by any account other than the owner.
                         */
                        modifier onlyOwner() {
                            require(msg.sender == _owner, "Ownable: caller is not the owner");
                            _;
                        }
                        /**
                         * @dev Allows the current owner to transfer control of the contract to a newOwner.
                         * @param newOwner The address to transfer ownership to.
                         */
                        function transferOwnership(address newOwner) external onlyOwner {
                            require(
                                newOwner != address(0),
                                "Ownable: new owner is the zero address"
                            );
                            emit OwnershipTransferred(_owner, newOwner);
                            setOwner(newOwner);
                        }
                    }
                    /**
                     * SPDX-License-Identifier: Apache-2.0
                     *
                     * Copyright (c) 2023, Circle Internet Financial, LLC.
                     *
                     * Licensed under the Apache License, Version 2.0 (the "License");
                     * you may not use this file except in compliance with the License.
                     * You may obtain a copy of the License at
                     *
                     * http://www.apache.org/licenses/LICENSE-2.0
                     *
                     * Unless required by applicable law or agreed to in writing, software
                     * distributed under the License is distributed on an "AS IS" BASIS,
                     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
                     * See the License for the specific language governing permissions and
                     * limitations under the License.
                     */
                    pragma solidity 0.6.12;
                    import { SafeMath } from "@openzeppelin/contracts/math/SafeMath.sol";
                    import { AbstractFiatTokenV1 } from "./AbstractFiatTokenV1.sol";
                    import { Ownable } from "./Ownable.sol";
                    import { Pausable } from "./Pausable.sol";
                    import { Blacklistable } from "./Blacklistable.sol";
                    /**
                     * @title FiatToken
                     * @dev ERC20 Token backed by fiat reserves
                     */
                    contract FiatTokenV1 is AbstractFiatTokenV1, Ownable, Pausable, Blacklistable {
                        using SafeMath for uint256;
                        string public name;
                        string public symbol;
                        uint8 public decimals;
                        string public currency;
                        address public masterMinter;
                        bool internal initialized;
                        /// @dev A mapping that stores the balance and blacklist states for a given address.
                        /// The first bit defines whether the address is blacklisted (1 if blacklisted, 0 otherwise).
                        /// The last 255 bits define the balance for the address.
                        mapping(address => uint256) internal balanceAndBlacklistStates;
                        mapping(address => mapping(address => uint256)) internal allowed;
                        uint256 internal totalSupply_ = 0;
                        mapping(address => bool) internal minters;
                        mapping(address => uint256) internal minterAllowed;
                        event Mint(address indexed minter, address indexed to, uint256 amount);
                        event Burn(address indexed burner, uint256 amount);
                        event MinterConfigured(address indexed minter, uint256 minterAllowedAmount);
                        event MinterRemoved(address indexed oldMinter);
                        event MasterMinterChanged(address indexed newMasterMinter);
                        /**
                         * @notice Initializes the fiat token contract.
                         * @param tokenName       The name of the fiat token.
                         * @param tokenSymbol     The symbol of the fiat token.
                         * @param tokenCurrency   The fiat currency that the token represents.
                         * @param tokenDecimals   The number of decimals that the token uses.
                         * @param newMasterMinter The masterMinter address for the fiat token.
                         * @param newPauser       The pauser address for the fiat token.
                         * @param newBlacklister  The blacklister address for the fiat token.
                         * @param newOwner        The owner of the fiat token.
                         */
                        function initialize(
                            string memory tokenName,
                            string memory tokenSymbol,
                            string memory tokenCurrency,
                            uint8 tokenDecimals,
                            address newMasterMinter,
                            address newPauser,
                            address newBlacklister,
                            address newOwner
                        ) public {
                            require(!initialized, "FiatToken: contract is already initialized");
                            require(
                                newMasterMinter != address(0),
                                "FiatToken: new masterMinter is the zero address"
                            );
                            require(
                                newPauser != address(0),
                                "FiatToken: new pauser is the zero address"
                            );
                            require(
                                newBlacklister != address(0),
                                "FiatToken: new blacklister is the zero address"
                            );
                            require(
                                newOwner != address(0),
                                "FiatToken: new owner is the zero address"
                            );
                            name = tokenName;
                            symbol = tokenSymbol;
                            currency = tokenCurrency;
                            decimals = tokenDecimals;
                            masterMinter = newMasterMinter;
                            pauser = newPauser;
                            blacklister = newBlacklister;
                            setOwner(newOwner);
                            initialized = true;
                        }
                        /**
                         * @dev Throws if called by any account other than a minter.
                         */
                        modifier onlyMinters() {
                            require(minters[msg.sender], "FiatToken: caller is not a minter");
                            _;
                        }
                        /**
                         * @notice Mints fiat tokens to an address.
                         * @param _to The address that will receive the minted tokens.
                         * @param _amount The amount of tokens to mint. Must be less than or equal
                         * to the minterAllowance of the caller.
                         * @return True if the operation was successful.
                         */
                        function mint(address _to, uint256 _amount)
                            external
                            whenNotPaused
                            onlyMinters
                            notBlacklisted(msg.sender)
                            notBlacklisted(_to)
                            returns (bool)
                        {
                            require(_to != address(0), "FiatToken: mint to the zero address");
                            require(_amount > 0, "FiatToken: mint amount not greater than 0");
                            uint256 mintingAllowedAmount = minterAllowed[msg.sender];
                            require(
                                _amount <= mintingAllowedAmount,
                                "FiatToken: mint amount exceeds minterAllowance"
                            );
                            totalSupply_ = totalSupply_.add(_amount);
                            _setBalance(_to, _balanceOf(_to).add(_amount));
                            minterAllowed[msg.sender] = mintingAllowedAmount.sub(_amount);
                            emit Mint(msg.sender, _to, _amount);
                            emit Transfer(address(0), _to, _amount);
                            return true;
                        }
                        /**
                         * @dev Throws if called by any account other than the masterMinter
                         */
                        modifier onlyMasterMinter() {
                            require(
                                msg.sender == masterMinter,
                                "FiatToken: caller is not the masterMinter"
                            );
                            _;
                        }
                        /**
                         * @notice Gets the minter allowance for an account.
                         * @param minter The address to check.
                         * @return The remaining minter allowance for the account.
                         */
                        function minterAllowance(address minter) external view returns (uint256) {
                            return minterAllowed[minter];
                        }
                        /**
                         * @notice Checks if an account is a minter.
                         * @param account The address to check.
                         * @return True if the account is a minter, false if the account is not a minter.
                         */
                        function isMinter(address account) external view returns (bool) {
                            return minters[account];
                        }
                        /**
                         * @notice Gets the remaining amount of fiat tokens a spender is allowed to transfer on
                         * behalf of the token owner.
                         * @param owner   The token owner's address.
                         * @param spender The spender's address.
                         * @return The remaining allowance.
                         */
                        function allowance(address owner, address spender)
                            external
                            override
                            view
                            returns (uint256)
                        {
                            return allowed[owner][spender];
                        }
                        /**
                         * @notice Gets the totalSupply of the fiat token.
                         * @return The totalSupply of the fiat token.
                         */
                        function totalSupply() external override view returns (uint256) {
                            return totalSupply_;
                        }
                        /**
                         * @notice Gets the fiat token balance of an account.
                         * @param account  The address to check.
                         * @return balance The fiat token balance of the account.
                         */
                        function balanceOf(address account)
                            external
                            override
                            view
                            returns (uint256)
                        {
                            return _balanceOf(account);
                        }
                        /**
                         * @notice Sets a fiat token allowance for a spender to spend on behalf of the caller.
                         * @param spender The spender's address.
                         * @param value   The allowance amount.
                         * @return True if the operation was successful.
                         */
                        function approve(address spender, uint256 value)
                            external
                            virtual
                            override
                            whenNotPaused
                            notBlacklisted(msg.sender)
                            notBlacklisted(spender)
                            returns (bool)
                        {
                            _approve(msg.sender, spender, value);
                            return true;
                        }
                        /**
                         * @dev Internal function to set allowance.
                         * @param owner     Token owner's address.
                         * @param spender   Spender's address.
                         * @param value     Allowance amount.
                         */
                        function _approve(
                            address owner,
                            address spender,
                            uint256 value
                        ) internal override {
                            require(owner != address(0), "ERC20: approve from the zero address");
                            require(spender != address(0), "ERC20: approve to the zero address");
                            allowed[owner][spender] = value;
                            emit Approval(owner, spender, value);
                        }
                        /**
                         * @notice Transfers tokens from an address to another by spending the caller's allowance.
                         * @dev The caller must have some fiat token allowance on the payer's tokens.
                         * @param from  Payer's address.
                         * @param to    Payee's address.
                         * @param value Transfer amount.
                         * @return True if the operation was successful.
                         */
                        function transferFrom(
                            address from,
                            address to,
                            uint256 value
                        )
                            external
                            override
                            whenNotPaused
                            notBlacklisted(msg.sender)
                            notBlacklisted(from)
                            notBlacklisted(to)
                            returns (bool)
                        {
                            require(
                                value <= allowed[from][msg.sender],
                                "ERC20: transfer amount exceeds allowance"
                            );
                            _transfer(from, to, value);
                            allowed[from][msg.sender] = allowed[from][msg.sender].sub(value);
                            return true;
                        }
                        /**
                         * @notice Transfers tokens from the caller.
                         * @param to    Payee's address.
                         * @param value Transfer amount.
                         * @return True if the operation was successful.
                         */
                        function transfer(address to, uint256 value)
                            external
                            override
                            whenNotPaused
                            notBlacklisted(msg.sender)
                            notBlacklisted(to)
                            returns (bool)
                        {
                            _transfer(msg.sender, to, value);
                            return true;
                        }
                        /**
                         * @dev Internal function to process transfers.
                         * @param from  Payer's address.
                         * @param to    Payee's address.
                         * @param value Transfer amount.
                         */
                        function _transfer(
                            address from,
                            address to,
                            uint256 value
                        ) internal override {
                            require(from != address(0), "ERC20: transfer from the zero address");
                            require(to != address(0), "ERC20: transfer to the zero address");
                            require(
                                value <= _balanceOf(from),
                                "ERC20: transfer amount exceeds balance"
                            );
                            _setBalance(from, _balanceOf(from).sub(value));
                            _setBalance(to, _balanceOf(to).add(value));
                            emit Transfer(from, to, value);
                        }
                        /**
                         * @notice Adds or updates a new minter with a mint allowance.
                         * @param minter The address of the minter.
                         * @param minterAllowedAmount The minting amount allowed for the minter.
                         * @return True if the operation was successful.
                         */
                        function configureMinter(address minter, uint256 minterAllowedAmount)
                            external
                            whenNotPaused
                            onlyMasterMinter
                            returns (bool)
                        {
                            minters[minter] = true;
                            minterAllowed[minter] = minterAllowedAmount;
                            emit MinterConfigured(minter, minterAllowedAmount);
                            return true;
                        }
                        /**
                         * @notice Removes a minter.
                         * @param minter The address of the minter to remove.
                         * @return True if the operation was successful.
                         */
                        function removeMinter(address minter)
                            external
                            onlyMasterMinter
                            returns (bool)
                        {
                            minters[minter] = false;
                            minterAllowed[minter] = 0;
                            emit MinterRemoved(minter);
                            return true;
                        }
                        /**
                         * @notice Allows a minter to burn some of its own tokens.
                         * @dev The caller must be a minter, must not be blacklisted, and the amount to burn
                         * should be less than or equal to the account's balance.
                         * @param _amount the amount of tokens to be burned.
                         */
                        function burn(uint256 _amount)
                            external
                            whenNotPaused
                            onlyMinters
                            notBlacklisted(msg.sender)
                        {
                            uint256 balance = _balanceOf(msg.sender);
                            require(_amount > 0, "FiatToken: burn amount not greater than 0");
                            require(balance >= _amount, "FiatToken: burn amount exceeds balance");
                            totalSupply_ = totalSupply_.sub(_amount);
                            _setBalance(msg.sender, balance.sub(_amount));
                            emit Burn(msg.sender, _amount);
                            emit Transfer(msg.sender, address(0), _amount);
                        }
                        /**
                         * @notice Updates the master minter address.
                         * @param _newMasterMinter The address of the new master minter.
                         */
                        function updateMasterMinter(address _newMasterMinter) external onlyOwner {
                            require(
                                _newMasterMinter != address(0),
                                "FiatToken: new masterMinter is the zero address"
                            );
                            masterMinter = _newMasterMinter;
                            emit MasterMinterChanged(masterMinter);
                        }
                        /**
                         * @inheritdoc Blacklistable
                         */
                        function _blacklist(address _account) internal override {
                            _setBlacklistState(_account, true);
                        }
                        /**
                         * @inheritdoc Blacklistable
                         */
                        function _unBlacklist(address _account) internal override {
                            _setBlacklistState(_account, false);
                        }
                        /**
                         * @dev Helper method that sets the blacklist state of an account.
                         * @param _account         The address of the account.
                         * @param _shouldBlacklist True if the account should be blacklisted, false if the account should be unblacklisted.
                         */
                        function _setBlacklistState(address _account, bool _shouldBlacklist)
                            internal
                            virtual
                        {
                            _deprecatedBlacklisted[_account] = _shouldBlacklist;
                        }
                        /**
                         * @dev Helper method that sets the balance of an account.
                         * @param _account The address of the account.
                         * @param _balance The new fiat token balance of the account.
                         */
                        function _setBalance(address _account, uint256 _balance) internal virtual {
                            balanceAndBlacklistStates[_account] = _balance;
                        }
                        /**
                         * @inheritdoc Blacklistable
                         */
                        function _isBlacklisted(address _account)
                            internal
                            virtual
                            override
                            view
                            returns (bool)
                        {
                            return _deprecatedBlacklisted[_account];
                        }
                        /**
                         * @dev Helper method to obtain the balance of an account.
                         * @param _account  The address of the account.
                         * @return          The fiat token balance of the account.
                         */
                        function _balanceOf(address _account)
                            internal
                            virtual
                            view
                            returns (uint256)
                        {
                            return balanceAndBlacklistStates[_account];
                        }
                    }
                    /**
                     * SPDX-License-Identifier: Apache-2.0
                     *
                     * Copyright (c) 2023, Circle Internet Financial, LLC.
                     *
                     * Licensed under the Apache License, Version 2.0 (the "License");
                     * you may not use this file except in compliance with the License.
                     * You may obtain a copy of the License at
                     *
                     * http://www.apache.org/licenses/LICENSE-2.0
                     *
                     * Unless required by applicable law or agreed to in writing, software
                     * distributed under the License is distributed on an "AS IS" BASIS,
                     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
                     * See the License for the specific language governing permissions and
                     * limitations under the License.
                     */
                    pragma solidity 0.6.12;
                    import { Ownable } from "./Ownable.sol";
                    /**
                     * @title Blacklistable Token
                     * @dev Allows accounts to be blacklisted by a "blacklister" role
                     */
                    abstract contract Blacklistable is Ownable {
                        address public blacklister;
                        mapping(address => bool) internal _deprecatedBlacklisted;
                        event Blacklisted(address indexed _account);
                        event UnBlacklisted(address indexed _account);
                        event BlacklisterChanged(address indexed newBlacklister);
                        /**
                         * @dev Throws if called by any account other than the blacklister.
                         */
                        modifier onlyBlacklister() {
                            require(
                                msg.sender == blacklister,
                                "Blacklistable: caller is not the blacklister"
                            );
                            _;
                        }
                        /**
                         * @dev Throws if argument account is blacklisted.
                         * @param _account The address to check.
                         */
                        modifier notBlacklisted(address _account) {
                            require(
                                !_isBlacklisted(_account),
                                "Blacklistable: account is blacklisted"
                            );
                            _;
                        }
                        /**
                         * @notice Checks if account is blacklisted.
                         * @param _account The address to check.
                         * @return True if the account is blacklisted, false if the account is not blacklisted.
                         */
                        function isBlacklisted(address _account) external view returns (bool) {
                            return _isBlacklisted(_account);
                        }
                        /**
                         * @notice Adds account to blacklist.
                         * @param _account The address to blacklist.
                         */
                        function blacklist(address _account) external onlyBlacklister {
                            _blacklist(_account);
                            emit Blacklisted(_account);
                        }
                        /**
                         * @notice Removes account from blacklist.
                         * @param _account The address to remove from the blacklist.
                         */
                        function unBlacklist(address _account) external onlyBlacklister {
                            _unBlacklist(_account);
                            emit UnBlacklisted(_account);
                        }
                        /**
                         * @notice Updates the blacklister address.
                         * @param _newBlacklister The address of the new blacklister.
                         */
                        function updateBlacklister(address _newBlacklister) external onlyOwner {
                            require(
                                _newBlacklister != address(0),
                                "Blacklistable: new blacklister is the zero address"
                            );
                            blacklister = _newBlacklister;
                            emit BlacklisterChanged(blacklister);
                        }
                        /**
                         * @dev Checks if account is blacklisted.
                         * @param _account The address to check.
                         * @return true if the account is blacklisted, false otherwise.
                         */
                        function _isBlacklisted(address _account)
                            internal
                            virtual
                            view
                            returns (bool);
                        /**
                         * @dev Helper method that blacklists an account.
                         * @param _account The address to blacklist.
                         */
                        function _blacklist(address _account) internal virtual;
                        /**
                         * @dev Helper method that unblacklists an account.
                         * @param _account The address to unblacklist.
                         */
                        function _unBlacklist(address _account) internal virtual;
                    }
                    /**
                     * SPDX-License-Identifier: Apache-2.0
                     *
                     * Copyright (c) 2023, Circle Internet Financial, LLC.
                     *
                     * Licensed under the Apache License, Version 2.0 (the "License");
                     * you may not use this file except in compliance with the License.
                     * You may obtain a copy of the License at
                     *
                     * http://www.apache.org/licenses/LICENSE-2.0
                     *
                     * Unless required by applicable law or agreed to in writing, software
                     * distributed under the License is distributed on an "AS IS" BASIS,
                     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
                     * See the License for the specific language governing permissions and
                     * limitations under the License.
                     */
                    pragma solidity 0.6.12;
                    import { IERC20 } from "@openzeppelin/contracts/token/ERC20/IERC20.sol";
                    abstract contract AbstractFiatTokenV1 is IERC20 {
                        function _approve(
                            address owner,
                            address spender,
                            uint256 value
                        ) internal virtual;
                        function _transfer(
                            address from,
                            address to,
                            uint256 value
                        ) internal virtual;
                    }
                    /**
                     * SPDX-License-Identifier: Apache-2.0
                     *
                     * Copyright (c) 2023, Circle Internet Financial, LLC.
                     *
                     * Licensed under the Apache License, Version 2.0 (the "License");
                     * you may not use this file except in compliance with the License.
                     * You may obtain a copy of the License at
                     *
                     * http://www.apache.org/licenses/LICENSE-2.0
                     *
                     * Unless required by applicable law or agreed to in writing, software
                     * distributed under the License is distributed on an "AS IS" BASIS,
                     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
                     * See the License for the specific language governing permissions and
                     * limitations under the License.
                     */
                    pragma solidity 0.6.12;
                    import { Ownable } from "../v1/Ownable.sol";
                    import { IERC20 } from "@openzeppelin/contracts/token/ERC20/IERC20.sol";
                    import { SafeERC20 } from "@openzeppelin/contracts/token/ERC20/SafeERC20.sol";
                    contract Rescuable is Ownable {
                        using SafeERC20 for IERC20;
                        address private _rescuer;
                        event RescuerChanged(address indexed newRescuer);
                        /**
                         * @notice Returns current rescuer
                         * @return Rescuer's address
                         */
                        function rescuer() external view returns (address) {
                            return _rescuer;
                        }
                        /**
                         * @notice Revert if called by any account other than the rescuer.
                         */
                        modifier onlyRescuer() {
                            require(msg.sender == _rescuer, "Rescuable: caller is not the rescuer");
                            _;
                        }
                        /**
                         * @notice Rescue ERC20 tokens locked up in this contract.
                         * @param tokenContract ERC20 token contract address
                         * @param to        Recipient address
                         * @param amount    Amount to withdraw
                         */
                        function rescueERC20(
                            IERC20 tokenContract,
                            address to,
                            uint256 amount
                        ) external onlyRescuer {
                            tokenContract.safeTransfer(to, amount);
                        }
                        /**
                         * @notice Updates the rescuer address.
                         * @param newRescuer The address of the new rescuer.
                         */
                        function updateRescuer(address newRescuer) external onlyOwner {
                            require(
                                newRescuer != address(0),
                                "Rescuable: new rescuer is the zero address"
                            );
                            _rescuer = newRescuer;
                            emit RescuerChanged(newRescuer);
                        }
                    }
                    /**
                     * SPDX-License-Identifier: Apache-2.0
                     *
                     * Copyright (c) 2023, Circle Internet Financial, LLC.
                     *
                     * Licensed under the Apache License, Version 2.0 (the "License");
                     * you may not use this file except in compliance with the License.
                     * You may obtain a copy of the License at
                     *
                     * http://www.apache.org/licenses/LICENSE-2.0
                     *
                     * Unless required by applicable law or agreed to in writing, software
                     * distributed under the License is distributed on an "AS IS" BASIS,
                     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
                     * See the License for the specific language governing permissions and
                     * limitations under the License.
                     */
                    pragma solidity 0.6.12;
                    import { FiatTokenV1 } from "../v1/FiatTokenV1.sol";
                    import { Rescuable } from "./Rescuable.sol";
                    /**
                     * @title FiatTokenV1_1
                     * @dev ERC20 Token backed by fiat reserves
                     */
                    contract FiatTokenV1_1 is FiatTokenV1, Rescuable {
                    }
                    /**
                     * SPDX-License-Identifier: Apache-2.0
                     *
                     * Copyright (c) 2023, Circle Internet Financial, LLC.
                     *
                     * Licensed under the Apache License, Version 2.0 (the "License");
                     * you may not use this file except in compliance with the License.
                     * You may obtain a copy of the License at
                     *
                     * http://www.apache.org/licenses/LICENSE-2.0
                     *
                     * Unless required by applicable law or agreed to in writing, software
                     * distributed under the License is distributed on an "AS IS" BASIS,
                     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
                     * See the License for the specific language governing permissions and
                     * limitations under the License.
                     */
                    pragma solidity 0.6.12;
                    import { ECRecover } from "./ECRecover.sol";
                    import { IERC1271 } from "../interface/IERC1271.sol";
                    /**
                     * @dev Signature verification helper that can be used instead of `ECRecover.recover` to seamlessly support both ECDSA
                     * signatures from externally owned accounts (EOAs) as well as ERC1271 signatures from smart contract wallets.
                     *
                     * Adapted from https://github.com/OpenZeppelin/openzeppelin-contracts/blob/21bb89ef5bfc789b9333eb05e3ba2b7b284ac77c/contracts/utils/cryptography/SignatureChecker.sol
                     */
                    library SignatureChecker {
                        /**
                         * @dev Checks if a signature is valid for a given signer and data hash. If the signer is a smart contract, the
                         * signature is validated against that smart contract using ERC1271, otherwise it's validated using `ECRecover.recover`.
                         * @param signer        Address of the claimed signer
                         * @param digest        Keccak-256 hash digest of the signed message
                         * @param signature     Signature byte array associated with hash
                         */
                        function isValidSignatureNow(
                            address signer,
                            bytes32 digest,
                            bytes memory signature
                        ) external view returns (bool) {
                            if (!isContract(signer)) {
                                return ECRecover.recover(digest, signature) == signer;
                            }
                            return isValidERC1271SignatureNow(signer, digest, signature);
                        }
                        /**
                         * @dev Checks if a signature is valid for a given signer and data hash. The signature is validated
                         * against the signer smart contract using ERC1271.
                         * @param signer        Address of the claimed signer
                         * @param digest        Keccak-256 hash digest of the signed message
                         * @param signature     Signature byte array associated with hash
                         *
                         * NOTE: Unlike ECDSA signatures, contract signatures are revocable, and the outcome of this function can thus
                         * change through time. It could return true at block N and false at block N+1 (or the opposite).
                         */
                        function isValidERC1271SignatureNow(
                            address signer,
                            bytes32 digest,
                            bytes memory signature
                        ) internal view returns (bool) {
                            (bool success, bytes memory result) = signer.staticcall(
                                abi.encodeWithSelector(
                                    IERC1271.isValidSignature.selector,
                                    digest,
                                    signature
                                )
                            );
                            return (success &&
                                result.length >= 32 &&
                                abi.decode(result, (bytes32)) ==
                                bytes32(IERC1271.isValidSignature.selector));
                        }
                        /**
                         * @dev Checks if the input address is a smart contract.
                         */
                        function isContract(address addr) internal view returns (bool) {
                            uint256 size;
                            assembly {
                                size := extcodesize(addr)
                            }
                            return size > 0;
                        }
                    }
                    /**
                     * SPDX-License-Identifier: Apache-2.0
                     *
                     * Copyright (c) 2023, Circle Internet Financial, LLC.
                     *
                     * Licensed under the Apache License, Version 2.0 (the "License");
                     * you may not use this file except in compliance with the License.
                     * You may obtain a copy of the License at
                     *
                     * http://www.apache.org/licenses/LICENSE-2.0
                     *
                     * Unless required by applicable law or agreed to in writing, software
                     * distributed under the License is distributed on an "AS IS" BASIS,
                     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
                     * See the License for the specific language governing permissions and
                     * limitations under the License.
                     */
                    pragma solidity 0.6.12;
                    /**
                     * @dev Signature message hash utilities for producing digests to be consumed by {ECDSA} recovery or signing.
                     *
                     * The library provides methods for generating a hash of a message that conforms to the
                     * https://eips.ethereum.org/EIPS/eip-191[EIP 191] and https://eips.ethereum.org/EIPS/eip-712[EIP 712]
                     * specifications.
                     */
                    library MessageHashUtils {
                        /**
                         * @dev Returns the keccak256 digest of an EIP-712 typed data (EIP-191 version `0x01`).
                         * Adapted from https://github.com/OpenZeppelin/openzeppelin-contracts/blob/21bb89ef5bfc789b9333eb05e3ba2b7b284ac77c/contracts/utils/cryptography/MessageHashUtils.sol
                         *
                         * The digest is calculated from a `domainSeparator` and a `structHash`, by prefixing them with
                         * `\\x19\\x01` and hashing the result. It corresponds to the hash signed by the
                         * https://eips.ethereum.org/EIPS/eip-712[`eth_signTypedData`] JSON-RPC method as part of EIP-712.
                         *
                         * @param domainSeparator    Domain separator
                         * @param structHash         Hashed EIP-712 data struct
                         * @return digest            The keccak256 digest of an EIP-712 typed data
                         */
                        function toTypedDataHash(bytes32 domainSeparator, bytes32 structHash)
                            internal
                            pure
                            returns (bytes32 digest)
                        {
                            assembly {
                                let ptr := mload(0x40)
                                mstore(ptr, "\\x19\\x01")
                                mstore(add(ptr, 0x02), domainSeparator)
                                mstore(add(ptr, 0x22), structHash)
                                digest := keccak256(ptr, 0x42)
                            }
                        }
                    }
                    /**
                     * SPDX-License-Identifier: Apache-2.0
                     *
                     * Copyright (c) 2023, Circle Internet Financial, LLC.
                     *
                     * Licensed under the Apache License, Version 2.0 (the "License");
                     * you may not use this file except in compliance with the License.
                     * You may obtain a copy of the License at
                     *
                     * http://www.apache.org/licenses/LICENSE-2.0
                     *
                     * Unless required by applicable law or agreed to in writing, software
                     * distributed under the License is distributed on an "AS IS" BASIS,
                     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
                     * See the License for the specific language governing permissions and
                     * limitations under the License.
                     */
                    pragma solidity 0.6.12;
                    /**
                     * @title EIP712
                     * @notice A library that provides EIP712 helper functions
                     */
                    library EIP712 {
                        /**
                         * @notice Make EIP712 domain separator
                         * @param name      Contract name
                         * @param version   Contract version
                         * @param chainId   Blockchain ID
                         * @return Domain separator
                         */
                        function makeDomainSeparator(
                            string memory name,
                            string memory version,
                            uint256 chainId
                        ) internal view returns (bytes32) {
                            return
                                keccak256(
                                    abi.encode(
                                        // keccak256("EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)")
                                        0x8b73c3c69bb8fe3d512ecc4cf759cc79239f7b179b0ffacaa9a75d522b39400f,
                                        keccak256(bytes(name)),
                                        keccak256(bytes(version)),
                                        chainId,
                                        address(this)
                                    )
                                );
                        }
                        /**
                         * @notice Make EIP712 domain separator
                         * @param name      Contract name
                         * @param version   Contract version
                         * @return Domain separator
                         */
                        function makeDomainSeparator(string memory name, string memory version)
                            internal
                            view
                            returns (bytes32)
                        {
                            uint256 chainId;
                            assembly {
                                chainId := chainid()
                            }
                            return makeDomainSeparator(name, version, chainId);
                        }
                    }
                    /**
                     * SPDX-License-Identifier: Apache-2.0
                     *
                     * Copyright (c) 2023, Circle Internet Financial, LLC.
                     *
                     * Licensed under the Apache License, Version 2.0 (the "License");
                     * you may not use this file except in compliance with the License.
                     * You may obtain a copy of the License at
                     *
                     * http://www.apache.org/licenses/LICENSE-2.0
                     *
                     * Unless required by applicable law or agreed to in writing, software
                     * distributed under the License is distributed on an "AS IS" BASIS,
                     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
                     * See the License for the specific language governing permissions and
                     * limitations under the License.
                     */
                    pragma solidity 0.6.12;
                    /**
                     * @title ECRecover
                     * @notice A library that provides a safe ECDSA recovery function
                     */
                    library ECRecover {
                        /**
                         * @notice Recover signer's address from a signed message
                         * @dev Adapted from: https://github.com/OpenZeppelin/openzeppelin-contracts/blob/65e4ffde586ec89af3b7e9140bdc9235d1254853/contracts/cryptography/ECDSA.sol
                         * Modifications: Accept v, r, and s as separate arguments
                         * @param digest    Keccak-256 hash digest of the signed message
                         * @param v         v of the signature
                         * @param r         r of the signature
                         * @param s         s of the signature
                         * @return Signer address
                         */
                        function recover(
                            bytes32 digest,
                            uint8 v,
                            bytes32 r,
                            bytes32 s
                        ) internal pure returns (address) {
                            // EIP-2 still allows signature malleability for ecrecover(). Remove this possibility and make the signature
                            // unique. Appendix F in the Ethereum Yellow paper (https://ethereum.github.io/yellowpaper/paper.pdf), defines
                            // the valid range for s in (281): 0 < s < secp256k1n ÷ 2 + 1, and for v in (282): v ∈ {27, 28}. Most
                            // signatures from current libraries generate a unique signature with an s-value in the lower half order.
                            //
                            // If your library generates malleable signatures, such as s-values in the upper range, calculate a new s-value
                            // with 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141 - s1 and flip v from 27 to 28 or
                            // vice versa. If your library also generates signatures with 0/1 for v instead 27/28, add 27 to v to accept
                            // these malleable signatures as well.
                            if (
                                uint256(s) >
                                0x7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF5D576E7357A4501DDFE92F46681B20A0
                            ) {
                                revert("ECRecover: invalid signature 's' value");
                            }
                            if (v != 27 && v != 28) {
                                revert("ECRecover: invalid signature 'v' value");
                            }
                            // If the signature is valid (and not malleable), return the signer address
                            address signer = ecrecover(digest, v, r, s);
                            require(signer != address(0), "ECRecover: invalid signature");
                            return signer;
                        }
                        /**
                         * @notice Recover signer's address from a signed message
                         * @dev Adapted from: https://github.com/OpenZeppelin/openzeppelin-contracts/blob/0053ee040a7ff1dbc39691c9e67a69f564930a88/contracts/utils/cryptography/ECDSA.sol
                         * @param digest    Keccak-256 hash digest of the signed message
                         * @param signature Signature byte array associated with hash
                         * @return Signer address
                         */
                        function recover(bytes32 digest, bytes memory signature)
                            internal
                            pure
                            returns (address)
                        {
                            require(signature.length == 65, "ECRecover: invalid signature length");
                            bytes32 r;
                            bytes32 s;
                            uint8 v;
                            // ecrecover takes the signature parameters, and the only way to get them
                            // currently is to use assembly.
                            /// @solidity memory-safe-assembly
                            assembly {
                                r := mload(add(signature, 0x20))
                                s := mload(add(signature, 0x40))
                                v := byte(0, mload(add(signature, 0x60)))
                            }
                            return recover(digest, v, r, s);
                        }
                    }
                    /**
                     * SPDX-License-Identifier: Apache-2.0
                     *
                     * Copyright (c) 2023, Circle Internet Financial, LLC.
                     *
                     * Licensed under the Apache License, Version 2.0 (the "License");
                     * you may not use this file except in compliance with the License.
                     * You may obtain a copy of the License at
                     *
                     * http://www.apache.org/licenses/LICENSE-2.0
                     *
                     * Unless required by applicable law or agreed to in writing, software
                     * distributed under the License is distributed on an "AS IS" BASIS,
                     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
                     * See the License for the specific language governing permissions and
                     * limitations under the License.
                     */
                    pragma solidity 0.6.12;
                    /**
                     * @dev Interface of the ERC1271 standard signature validation method for
                     * contracts as defined in https://eips.ethereum.org/EIPS/eip-1271[ERC-1271].
                     */
                    interface IERC1271 {
                        /**
                         * @dev Should return whether the signature provided is valid for the provided data
                         * @param hash          Hash of the data to be signed
                         * @param signature     Signature byte array associated with the provided data hash
                         * @return magicValue   bytes4 magic value 0x1626ba7e when function passes
                         */
                        function isValidSignature(bytes32 hash, bytes memory signature)
                            external
                            view
                            returns (bytes4 magicValue);
                    }
                    

                    File 8 of 11: AddressManager
                    // SPDX-License-Identifier: MIT
                    pragma solidity 0.8.15;
                    import { Ownable } from "@openzeppelin/contracts/access/Ownable.sol";
                    /**
                     * @custom:legacy
                     * @title AddressManager
                     * @notice AddressManager is a legacy contract that was used in the old version of the Optimism
                     *         system to manage a registry of string names to addresses. We now use a more standard
                     *         proxy system instead, but this contract is still necessary for backwards compatibility
                     *         with several older contracts.
                     */
                    contract AddressManager is Ownable {
                        /**
                         * @notice Mapping of the hashes of string names to addresses.
                         */
                        mapping(bytes32 => address) private addresses;
                        /**
                         * @notice Emitted when an address is modified in the registry.
                         *
                         * @param name       String name being set in the registry.
                         * @param newAddress Address set for the given name.
                         * @param oldAddress Address that was previously set for the given name.
                         */
                        event AddressSet(string indexed name, address newAddress, address oldAddress);
                        /**
                         * @notice Changes the address associated with a particular name.
                         *
                         * @param _name    String name to associate an address with.
                         * @param _address Address to associate with the name.
                         */
                        function setAddress(string memory _name, address _address) external onlyOwner {
                            bytes32 nameHash = _getNameHash(_name);
                            address oldAddress = addresses[nameHash];
                            addresses[nameHash] = _address;
                            emit AddressSet(_name, _address, oldAddress);
                        }
                        /**
                         * @notice Retrieves the address associated with a given name.
                         *
                         * @param _name Name to retrieve an address for.
                         *
                         * @return Address associated with the given name.
                         */
                        function getAddress(string memory _name) external view returns (address) {
                            return addresses[_getNameHash(_name)];
                        }
                        /**
                         * @notice Computes the hash of a name.
                         *
                         * @param _name Name to compute a hash for.
                         *
                         * @return Hash of the given name.
                         */
                        function _getNameHash(string memory _name) internal pure returns (bytes32) {
                            return keccak256(abi.encodePacked(_name));
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    // OpenZeppelin Contracts (last updated v4.7.0) (access/Ownable.sol)
                    pragma solidity ^0.8.0;
                    import "../utils/Context.sol";
                    /**
                     * @dev Contract module which provides a basic access control mechanism, where
                     * there is an account (an owner) that can be granted exclusive access to
                     * specific functions.
                     *
                     * By default, the owner account will be the one that deploys the contract. This
                     * can later be changed with {transferOwnership}.
                     *
                     * This module is used through inheritance. It will make available the modifier
                     * `onlyOwner`, which can be applied to your functions to restrict their use to
                     * the owner.
                     */
                    abstract contract Ownable is Context {
                        address private _owner;
                        event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
                        /**
                         * @dev Initializes the contract setting the deployer as the initial owner.
                         */
                        constructor() {
                            _transferOwnership(_msgSender());
                        }
                        /**
                         * @dev Throws if called by any account other than the owner.
                         */
                        modifier onlyOwner() {
                            _checkOwner();
                            _;
                        }
                        /**
                         * @dev Returns the address of the current owner.
                         */
                        function owner() public view virtual returns (address) {
                            return _owner;
                        }
                        /**
                         * @dev Throws if the sender is not the owner.
                         */
                        function _checkOwner() internal view virtual {
                            require(owner() == _msgSender(), "Ownable: caller is not the owner");
                        }
                        /**
                         * @dev Leaves the contract without owner. It will not be possible to call
                         * `onlyOwner` functions anymore. Can only be called by the current owner.
                         *
                         * NOTE: Renouncing ownership will leave the contract without an owner,
                         * thereby removing any functionality that is only available to the owner.
                         */
                        function renounceOwnership() public virtual onlyOwner {
                            _transferOwnership(address(0));
                        }
                        /**
                         * @dev Transfers ownership of the contract to a new account (`newOwner`).
                         * Can only be called by the current owner.
                         */
                        function transferOwnership(address newOwner) public virtual onlyOwner {
                            require(newOwner != address(0), "Ownable: new owner is the zero address");
                            _transferOwnership(newOwner);
                        }
                        /**
                         * @dev Transfers ownership of the contract to a new account (`newOwner`).
                         * Internal function without access restriction.
                         */
                        function _transferOwnership(address newOwner) internal virtual {
                            address oldOwner = _owner;
                            _owner = newOwner;
                            emit OwnershipTransferred(oldOwner, newOwner);
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    // OpenZeppelin Contracts v4.4.1 (utils/Context.sol)
                    pragma solidity ^0.8.0;
                    /**
                     * @dev Provides information about the current execution context, including the
                     * sender of the transaction and its data. While these are generally available
                     * via msg.sender and msg.data, they should not be accessed in such a direct
                     * manner, since when dealing with meta-transactions the account sending and
                     * paying for execution may not be the actual sender (as far as an application
                     * is concerned).
                     *
                     * This contract is only required for intermediate, library-like contracts.
                     */
                    abstract contract Context {
                        function _msgSender() internal view virtual returns (address) {
                            return msg.sender;
                        }
                        function _msgData() internal view virtual returns (bytes calldata) {
                            return msg.data;
                        }
                    }
                    

                    File 9 of 11: L1CrossDomainMessenger
                    // SPDX-License-Identifier: MIT
                    pragma solidity 0.8.15;
                    import { Predeploys } from "../libraries/Predeploys.sol";
                    import { OptimismPortal } from "./OptimismPortal.sol";
                    import { CrossDomainMessenger } from "../universal/CrossDomainMessenger.sol";
                    import { Semver } from "../universal/Semver.sol";
                    /**
                     * @custom:proxied
                     * @title L1CrossDomainMessenger
                     * @notice The L1CrossDomainMessenger is a message passing interface between L1 and L2 responsible
                     *         for sending and receiving data on the L1 side. Users are encouraged to use this
                     *         interface instead of interacting with lower-level contracts directly.
                     */
                    contract L1CrossDomainMessenger is CrossDomainMessenger, Semver {
                        /**
                         * @notice Address of the OptimismPortal.
                         */
                        OptimismPortal public immutable PORTAL;
                        /**
                         * @custom:semver 1.4.0
                         *
                         * @param _portal Address of the OptimismPortal contract on this network.
                         */
                        constructor(OptimismPortal _portal)
                            Semver(1, 4, 0)
                            CrossDomainMessenger(Predeploys.L2_CROSS_DOMAIN_MESSENGER)
                        {
                            PORTAL = _portal;
                            initialize();
                        }
                        /**
                         * @notice Initializer.
                         */
                        function initialize() public initializer {
                            __CrossDomainMessenger_init();
                        }
                        /**
                         * @inheritdoc CrossDomainMessenger
                         */
                        function _sendMessage(
                            address _to,
                            uint64 _gasLimit,
                            uint256 _value,
                            bytes memory _data
                        ) internal override {
                            PORTAL.depositTransaction{ value: _value }(_to, _value, _gasLimit, false, _data);
                        }
                        /**
                         * @inheritdoc CrossDomainMessenger
                         */
                        function _isOtherMessenger() internal view override returns (bool) {
                            return msg.sender == address(PORTAL) && PORTAL.l2Sender() == OTHER_MESSENGER;
                        }
                        /**
                         * @inheritdoc CrossDomainMessenger
                         */
                        function _isUnsafeTarget(address _target) internal view override returns (bool) {
                            return _target == address(this) || _target == address(PORTAL);
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    pragma solidity 0.8.15;
                    import { Initializable } from "@openzeppelin/contracts/proxy/utils/Initializable.sol";
                    import { Semver } from "../universal/Semver.sol";
                    import { Types } from "../libraries/Types.sol";
                    /**
                     * @custom:proxied
                     * @title L2OutputOracle
                     * @notice The L2OutputOracle contains an array of L2 state outputs, where each output is a
                     *         commitment to the state of the L2 chain. Other contracts like the OptimismPortal use
                     *         these outputs to verify information about the state of L2.
                     */
                    contract L2OutputOracle is Initializable, Semver {
                        /**
                         * @notice The interval in L2 blocks at which checkpoints must be submitted. Although this is
                         *         immutable, it can safely be modified by upgrading the implementation contract.
                         */
                        uint256 public immutable SUBMISSION_INTERVAL;
                        /**
                         * @notice The time between L2 blocks in seconds. Once set, this value MUST NOT be modified.
                         */
                        uint256 public immutable L2_BLOCK_TIME;
                        /**
                         * @notice The address of the challenger. Can be updated via upgrade.
                         */
                        address public immutable CHALLENGER;
                        /**
                         * @notice The address of the proposer. Can be updated via upgrade.
                         */
                        address public immutable PROPOSER;
                        /**
                         * @notice Minimum time (in seconds) that must elapse before a withdrawal can be finalized.
                         */
                        uint256 public immutable FINALIZATION_PERIOD_SECONDS;
                        /**
                         * @notice The number of the first L2 block recorded in this contract.
                         */
                        uint256 public startingBlockNumber;
                        /**
                         * @notice The timestamp of the first L2 block recorded in this contract.
                         */
                        uint256 public startingTimestamp;
                        /**
                         * @notice Array of L2 output proposals.
                         */
                        Types.OutputProposal[] internal l2Outputs;
                        /**
                         * @notice Emitted when an output is proposed.
                         *
                         * @param outputRoot    The output root.
                         * @param l2OutputIndex The index of the output in the l2Outputs array.
                         * @param l2BlockNumber The L2 block number of the output root.
                         * @param l1Timestamp   The L1 timestamp when proposed.
                         */
                        event OutputProposed(
                            bytes32 indexed outputRoot,
                            uint256 indexed l2OutputIndex,
                            uint256 indexed l2BlockNumber,
                            uint256 l1Timestamp
                        );
                        /**
                         * @notice Emitted when outputs are deleted.
                         *
                         * @param prevNextOutputIndex Next L2 output index before the deletion.
                         * @param newNextOutputIndex  Next L2 output index after the deletion.
                         */
                        event OutputsDeleted(uint256 indexed prevNextOutputIndex, uint256 indexed newNextOutputIndex);
                        /**
                         * @custom:semver 1.3.0
                         *
                         * @param _submissionInterval  Interval in blocks at which checkpoints must be submitted.
                         * @param _l2BlockTime         The time per L2 block, in seconds.
                         * @param _startingBlockNumber The number of the first L2 block.
                         * @param _startingTimestamp   The timestamp of the first L2 block.
                         * @param _proposer            The address of the proposer.
                         * @param _challenger          The address of the challenger.
                         */
                        constructor(
                            uint256 _submissionInterval,
                            uint256 _l2BlockTime,
                            uint256 _startingBlockNumber,
                            uint256 _startingTimestamp,
                            address _proposer,
                            address _challenger,
                            uint256 _finalizationPeriodSeconds
                        ) Semver(1, 3, 0) {
                            require(_l2BlockTime > 0, "L2OutputOracle: L2 block time must be greater than 0");
                            require(
                                _submissionInterval > 0,
                                "L2OutputOracle: submission interval must be greater than 0"
                            );
                            SUBMISSION_INTERVAL = _submissionInterval;
                            L2_BLOCK_TIME = _l2BlockTime;
                            PROPOSER = _proposer;
                            CHALLENGER = _challenger;
                            FINALIZATION_PERIOD_SECONDS = _finalizationPeriodSeconds;
                            initialize(_startingBlockNumber, _startingTimestamp);
                        }
                        /**
                         * @notice Initializer.
                         *
                         * @param _startingBlockNumber Block number for the first recoded L2 block.
                         * @param _startingTimestamp   Timestamp for the first recoded L2 block.
                         */
                        function initialize(uint256 _startingBlockNumber, uint256 _startingTimestamp)
                            public
                            initializer
                        {
                            require(
                                _startingTimestamp <= block.timestamp,
                                "L2OutputOracle: starting L2 timestamp must be less than current time"
                            );
                            startingTimestamp = _startingTimestamp;
                            startingBlockNumber = _startingBlockNumber;
                        }
                        /**
                         * @notice Deletes all output proposals after and including the proposal that corresponds to
                         *         the given output index. Only the challenger address can delete outputs.
                         *
                         * @param _l2OutputIndex Index of the first L2 output to be deleted. All outputs after this
                         *                       output will also be deleted.
                         */
                        // solhint-disable-next-line ordering
                        function deleteL2Outputs(uint256 _l2OutputIndex) external {
                            require(
                                msg.sender == CHALLENGER,
                                "L2OutputOracle: only the challenger address can delete outputs"
                            );
                            // Make sure we're not *increasing* the length of the array.
                            require(
                                _l2OutputIndex < l2Outputs.length,
                                "L2OutputOracle: cannot delete outputs after the latest output index"
                            );
                            // Do not allow deleting any outputs that have already been finalized.
                            require(
                                block.timestamp - l2Outputs[_l2OutputIndex].timestamp < FINALIZATION_PERIOD_SECONDS,
                                "L2OutputOracle: cannot delete outputs that have already been finalized"
                            );
                            uint256 prevNextL2OutputIndex = nextOutputIndex();
                            // Use assembly to delete the array elements because Solidity doesn't allow it.
                            assembly {
                                sstore(l2Outputs.slot, _l2OutputIndex)
                            }
                            emit OutputsDeleted(prevNextL2OutputIndex, _l2OutputIndex);
                        }
                        /**
                         * @notice Accepts an outputRoot and the timestamp of the corresponding L2 block. The timestamp
                         *         must be equal to the current value returned by `nextTimestamp()` in order to be
                         *         accepted. This function may only be called by the Proposer.
                         *
                         * @param _outputRoot    The L2 output of the checkpoint block.
                         * @param _l2BlockNumber The L2 block number that resulted in _outputRoot.
                         * @param _l1BlockHash   A block hash which must be included in the current chain.
                         * @param _l1BlockNumber The block number with the specified block hash.
                         */
                        function proposeL2Output(
                            bytes32 _outputRoot,
                            uint256 _l2BlockNumber,
                            bytes32 _l1BlockHash,
                            uint256 _l1BlockNumber
                        ) external payable {
                            require(
                                msg.sender == PROPOSER,
                                "L2OutputOracle: only the proposer address can propose new outputs"
                            );
                            require(
                                _l2BlockNumber == nextBlockNumber(),
                                "L2OutputOracle: block number must be equal to next expected block number"
                            );
                            require(
                                computeL2Timestamp(_l2BlockNumber) < block.timestamp,
                                "L2OutputOracle: cannot propose L2 output in the future"
                            );
                            require(
                                _outputRoot != bytes32(0),
                                "L2OutputOracle: L2 output proposal cannot be the zero hash"
                            );
                            if (_l1BlockHash != bytes32(0)) {
                                // This check allows the proposer to propose an output based on a given L1 block,
                                // without fear that it will be reorged out.
                                // It will also revert if the blockheight provided is more than 256 blocks behind the
                                // chain tip (as the hash will return as zero). This does open the door to a griefing
                                // attack in which the proposer's submission is censored until the block is no longer
                                // retrievable, if the proposer is experiencing this attack it can simply leave out the
                                // blockhash value, and delay submission until it is confident that the L1 block is
                                // finalized.
                                require(
                                    blockhash(_l1BlockNumber) == _l1BlockHash,
                                    "L2OutputOracle: block hash does not match the hash at the expected height"
                                );
                            }
                            emit OutputProposed(_outputRoot, nextOutputIndex(), _l2BlockNumber, block.timestamp);
                            l2Outputs.push(
                                Types.OutputProposal({
                                    outputRoot: _outputRoot,
                                    timestamp: uint128(block.timestamp),
                                    l2BlockNumber: uint128(_l2BlockNumber)
                                })
                            );
                        }
                        /**
                         * @notice Returns an output by index. Exists because Solidity's array access will return a
                         *         tuple instead of a struct.
                         *
                         * @param _l2OutputIndex Index of the output to return.
                         *
                         * @return The output at the given index.
                         */
                        function getL2Output(uint256 _l2OutputIndex)
                            external
                            view
                            returns (Types.OutputProposal memory)
                        {
                            return l2Outputs[_l2OutputIndex];
                        }
                        /**
                         * @notice Returns the index of the L2 output that checkpoints a given L2 block number. Uses a
                         *         binary search to find the first output greater than or equal to the given block.
                         *
                         * @param _l2BlockNumber L2 block number to find a checkpoint for.
                         *
                         * @return Index of the first checkpoint that commits to the given L2 block number.
                         */
                        function getL2OutputIndexAfter(uint256 _l2BlockNumber) public view returns (uint256) {
                            // Make sure an output for this block number has actually been proposed.
                            require(
                                _l2BlockNumber <= latestBlockNumber(),
                                "L2OutputOracle: cannot get output for a block that has not been proposed"
                            );
                            // Make sure there's at least one output proposed.
                            require(
                                l2Outputs.length > 0,
                                "L2OutputOracle: cannot get output as no outputs have been proposed yet"
                            );
                            // Find the output via binary search, guaranteed to exist.
                            uint256 lo = 0;
                            uint256 hi = l2Outputs.length;
                            while (lo < hi) {
                                uint256 mid = (lo + hi) / 2;
                                if (l2Outputs[mid].l2BlockNumber < _l2BlockNumber) {
                                    lo = mid + 1;
                                } else {
                                    hi = mid;
                                }
                            }
                            return lo;
                        }
                        /**
                         * @notice Returns the L2 output proposal that checkpoints a given L2 block number. Uses a
                         *         binary search to find the first output greater than or equal to the given block.
                         *
                         * @param _l2BlockNumber L2 block number to find a checkpoint for.
                         *
                         * @return First checkpoint that commits to the given L2 block number.
                         */
                        function getL2OutputAfter(uint256 _l2BlockNumber)
                            external
                            view
                            returns (Types.OutputProposal memory)
                        {
                            return l2Outputs[getL2OutputIndexAfter(_l2BlockNumber)];
                        }
                        /**
                         * @notice Returns the number of outputs that have been proposed. Will revert if no outputs
                         *         have been proposed yet.
                         *
                         * @return The number of outputs that have been proposed.
                         */
                        function latestOutputIndex() external view returns (uint256) {
                            return l2Outputs.length - 1;
                        }
                        /**
                         * @notice Returns the index of the next output to be proposed.
                         *
                         * @return The index of the next output to be proposed.
                         */
                        function nextOutputIndex() public view returns (uint256) {
                            return l2Outputs.length;
                        }
                        /**
                         * @notice Returns the block number of the latest submitted L2 output proposal. If no proposals
                         *         been submitted yet then this function will return the starting block number.
                         *
                         * @return Latest submitted L2 block number.
                         */
                        function latestBlockNumber() public view returns (uint256) {
                            return
                                l2Outputs.length == 0
                                    ? startingBlockNumber
                                    : l2Outputs[l2Outputs.length - 1].l2BlockNumber;
                        }
                        /**
                         * @notice Computes the block number of the next L2 block that needs to be checkpointed.
                         *
                         * @return Next L2 block number.
                         */
                        function nextBlockNumber() public view returns (uint256) {
                            return latestBlockNumber() + SUBMISSION_INTERVAL;
                        }
                        /**
                         * @notice Returns the L2 timestamp corresponding to a given L2 block number.
                         *
                         * @param _l2BlockNumber The L2 block number of the target block.
                         *
                         * @return L2 timestamp of the given block.
                         */
                        function computeL2Timestamp(uint256 _l2BlockNumber) public view returns (uint256) {
                            return startingTimestamp + ((_l2BlockNumber - startingBlockNumber) * L2_BLOCK_TIME);
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    pragma solidity 0.8.15;
                    import { Initializable } from "@openzeppelin/contracts/proxy/utils/Initializable.sol";
                    import { SafeCall } from "../libraries/SafeCall.sol";
                    import { L2OutputOracle } from "./L2OutputOracle.sol";
                    import { SystemConfig } from "./SystemConfig.sol";
                    import { Constants } from "../libraries/Constants.sol";
                    import { Types } from "../libraries/Types.sol";
                    import { Hashing } from "../libraries/Hashing.sol";
                    import { SecureMerkleTrie } from "../libraries/trie/SecureMerkleTrie.sol";
                    import { AddressAliasHelper } from "../vendor/AddressAliasHelper.sol";
                    import { ResourceMetering } from "./ResourceMetering.sol";
                    import { Semver } from "../universal/Semver.sol";
                    /**
                     * @custom:proxied
                     * @title OptimismPortal
                     * @notice The OptimismPortal is a low-level contract responsible for passing messages between L1
                     *         and L2. Messages sent directly to the OptimismPortal have no form of replayability.
                     *         Users are encouraged to use the L1CrossDomainMessenger for a higher-level interface.
                     */
                    contract OptimismPortal is Initializable, ResourceMetering, Semver {
                        /**
                         * @notice Represents a proven withdrawal.
                         *
                         * @custom:field outputRoot    Root of the L2 output this was proven against.
                         * @custom:field timestamp     Timestamp at whcih the withdrawal was proven.
                         * @custom:field l2OutputIndex Index of the output this was proven against.
                         */
                        struct ProvenWithdrawal {
                            bytes32 outputRoot;
                            uint128 timestamp;
                            uint128 l2OutputIndex;
                        }
                        /**
                         * @notice Version of the deposit event.
                         */
                        uint256 internal constant DEPOSIT_VERSION = 0;
                        /**
                         * @notice The L2 gas limit set when eth is deposited using the receive() function.
                         */
                        uint64 internal constant RECEIVE_DEFAULT_GAS_LIMIT = 100_000;
                        /**
                         * @notice Address of the L2OutputOracle contract.
                         */
                        L2OutputOracle public immutable L2_ORACLE;
                        /**
                         * @notice Address of the SystemConfig contract.
                         */
                        SystemConfig public immutable SYSTEM_CONFIG;
                        /**
                         * @notice Address that has the ability to pause and unpause withdrawals.
                         */
                        address public immutable GUARDIAN;
                        /**
                         * @notice Address of the L2 account which initiated a withdrawal in this transaction. If the
                         *         of this variable is the default L2 sender address, then we are NOT inside of a call
                         *         to finalizeWithdrawalTransaction.
                         */
                        address public l2Sender;
                        /**
                         * @notice A list of withdrawal hashes which have been successfully finalized.
                         */
                        mapping(bytes32 => bool) public finalizedWithdrawals;
                        /**
                         * @notice A mapping of withdrawal hashes to `ProvenWithdrawal` data.
                         */
                        mapping(bytes32 => ProvenWithdrawal) public provenWithdrawals;
                        /**
                         * @notice Determines if cross domain messaging is paused. When set to true,
                         *         withdrawals are paused. This may be removed in the future.
                         */
                        bool public paused;
                        /**
                         * @notice Emitted when a transaction is deposited from L1 to L2. The parameters of this event
                         *         are read by the rollup node and used to derive deposit transactions on L2.
                         *
                         * @param from       Address that triggered the deposit transaction.
                         * @param to         Address that the deposit transaction is directed to.
                         * @param version    Version of this deposit transaction event.
                         * @param opaqueData ABI encoded deposit data to be parsed off-chain.
                         */
                        event TransactionDeposited(
                            address indexed from,
                            address indexed to,
                            uint256 indexed version,
                            bytes opaqueData
                        );
                        /**
                         * @notice Emitted when a withdrawal transaction is proven.
                         *
                         * @param withdrawalHash Hash of the withdrawal transaction.
                         */
                        event WithdrawalProven(
                            bytes32 indexed withdrawalHash,
                            address indexed from,
                            address indexed to
                        );
                        /**
                         * @notice Emitted when a withdrawal transaction is finalized.
                         *
                         * @param withdrawalHash Hash of the withdrawal transaction.
                         * @param success        Whether the withdrawal transaction was successful.
                         */
                        event WithdrawalFinalized(bytes32 indexed withdrawalHash, bool success);
                        /**
                         * @notice Emitted when the pause is triggered.
                         *
                         * @param account Address of the account triggering the pause.
                         */
                        event Paused(address account);
                        /**
                         * @notice Emitted when the pause is lifted.
                         *
                         * @param account Address of the account triggering the unpause.
                         */
                        event Unpaused(address account);
                        /**
                         * @notice Reverts when paused.
                         */
                        modifier whenNotPaused() {
                            require(paused == false, "OptimismPortal: paused");
                            _;
                        }
                        /**
                         * @custom:semver 1.6.0
                         *
                         * @param _l2Oracle                  Address of the L2OutputOracle contract.
                         * @param _guardian                  Address that can pause deposits and withdrawals.
                         * @param _paused                    Sets the contract's pausability state.
                         * @param _config                    Address of the SystemConfig contract.
                         */
                        constructor(
                            L2OutputOracle _l2Oracle,
                            address _guardian,
                            bool _paused,
                            SystemConfig _config
                        ) Semver(1, 6, 0) {
                            L2_ORACLE = _l2Oracle;
                            GUARDIAN = _guardian;
                            SYSTEM_CONFIG = _config;
                            initialize(_paused);
                        }
                        /**
                         * @notice Initializer.
                         */
                        function initialize(bool _paused) public initializer {
                            l2Sender = Constants.DEFAULT_L2_SENDER;
                            paused = _paused;
                            __ResourceMetering_init();
                        }
                        /**
                         * @notice Pause deposits and withdrawals.
                         */
                        function pause() external {
                            require(msg.sender == GUARDIAN, "OptimismPortal: only guardian can pause");
                            paused = true;
                            emit Paused(msg.sender);
                        }
                        /**
                         * @notice Unpause deposits and withdrawals.
                         */
                        function unpause() external {
                            require(msg.sender == GUARDIAN, "OptimismPortal: only guardian can unpause");
                            paused = false;
                            emit Unpaused(msg.sender);
                        }
                        /**
                         * @notice Computes the minimum gas limit for a deposit. The minimum gas limit
                         *         linearly increases based on the size of the calldata. This is to prevent
                         *         users from creating L2 resource usage without paying for it. This function
                         *         can be used when interacting with the portal to ensure forwards compatibility.
                         *
                         */
                        function minimumGasLimit(uint64 _byteCount) public pure returns (uint64) {
                            return _byteCount * 16 + 21000;
                        }
                        /**
                         * @notice Accepts value so that users can send ETH directly to this contract and have the
                         *         funds be deposited to their address on L2. This is intended as a convenience
                         *         function for EOAs. Contracts should call the depositTransaction() function directly
                         *         otherwise any deposited funds will be lost due to address aliasing.
                         */
                        // solhint-disable-next-line ordering
                        receive() external payable {
                            depositTransaction(msg.sender, msg.value, RECEIVE_DEFAULT_GAS_LIMIT, false, bytes(""));
                        }
                        /**
                         * @notice Accepts ETH value without triggering a deposit to L2. This function mainly exists
                         *         for the sake of the migration between the legacy Optimism system and Bedrock.
                         */
                        function donateETH() external payable {
                            // Intentionally empty.
                        }
                        /**
                         * @notice Getter for the resource config. Used internally by the ResourceMetering
                         *         contract. The SystemConfig is the source of truth for the resource config.
                         *
                         * @return ResourceMetering.ResourceConfig
                         */
                        function _resourceConfig()
                            internal
                            view
                            override
                            returns (ResourceMetering.ResourceConfig memory)
                        {
                            return SYSTEM_CONFIG.resourceConfig();
                        }
                        /**
                         * @notice Proves a withdrawal transaction.
                         *
                         * @param _tx              Withdrawal transaction to finalize.
                         * @param _l2OutputIndex   L2 output index to prove against.
                         * @param _outputRootProof Inclusion proof of the L2ToL1MessagePasser contract's storage root.
                         * @param _withdrawalProof Inclusion proof of the withdrawal in L2ToL1MessagePasser contract.
                         */
                        function proveWithdrawalTransaction(
                            Types.WithdrawalTransaction memory _tx,
                            uint256 _l2OutputIndex,
                            Types.OutputRootProof calldata _outputRootProof,
                            bytes[] calldata _withdrawalProof
                        ) external whenNotPaused {
                            // Prevent users from creating a deposit transaction where this address is the message
                            // sender on L2. Because this is checked here, we do not need to check again in
                            // `finalizeWithdrawalTransaction`.
                            require(
                                _tx.target != address(this),
                                "OptimismPortal: you cannot send messages to the portal contract"
                            );
                            // Get the output root and load onto the stack to prevent multiple mloads. This will
                            // revert if there is no output root for the given block number.
                            bytes32 outputRoot = L2_ORACLE.getL2Output(_l2OutputIndex).outputRoot;
                            // Verify that the output root can be generated with the elements in the proof.
                            require(
                                outputRoot == Hashing.hashOutputRootProof(_outputRootProof),
                                "OptimismPortal: invalid output root proof"
                            );
                            // Load the ProvenWithdrawal into memory, using the withdrawal hash as a unique identifier.
                            bytes32 withdrawalHash = Hashing.hashWithdrawal(_tx);
                            ProvenWithdrawal memory provenWithdrawal = provenWithdrawals[withdrawalHash];
                            // We generally want to prevent users from proving the same withdrawal multiple times
                            // because each successive proof will update the timestamp. A malicious user can take
                            // advantage of this to prevent other users from finalizing their withdrawal. However,
                            // since withdrawals are proven before an output root is finalized, we need to allow users
                            // to re-prove their withdrawal only in the case that the output root for their specified
                            // output index has been updated.
                            require(
                                provenWithdrawal.timestamp == 0 ||
                                    L2_ORACLE.getL2Output(provenWithdrawal.l2OutputIndex).outputRoot !=
                                    provenWithdrawal.outputRoot,
                                "OptimismPortal: withdrawal hash has already been proven"
                            );
                            // Compute the storage slot of the withdrawal hash in the L2ToL1MessagePasser contract.
                            // Refer to the Solidity documentation for more information on how storage layouts are
                            // computed for mappings.
                            bytes32 storageKey = keccak256(
                                abi.encode(
                                    withdrawalHash,
                                    uint256(0) // The withdrawals mapping is at the first slot in the layout.
                                )
                            );
                            // Verify that the hash of this withdrawal was stored in the L2toL1MessagePasser contract
                            // on L2. If this is true, under the assumption that the SecureMerkleTrie does not have
                            // bugs, then we know that this withdrawal was actually triggered on L2 and can therefore
                            // be relayed on L1.
                            require(
                                SecureMerkleTrie.verifyInclusionProof(
                                    abi.encode(storageKey),
                                    hex"01",
                                    _withdrawalProof,
                                    _outputRootProof.messagePasserStorageRoot
                                ),
                                "OptimismPortal: invalid withdrawal inclusion proof"
                            );
                            // Designate the withdrawalHash as proven by storing the `outputRoot`, `timestamp`, and
                            // `l2BlockNumber` in the `provenWithdrawals` mapping. A `withdrawalHash` can only be
                            // proven once unless it is submitted again with a different outputRoot.
                            provenWithdrawals[withdrawalHash] = ProvenWithdrawal({
                                outputRoot: outputRoot,
                                timestamp: uint128(block.timestamp),
                                l2OutputIndex: uint128(_l2OutputIndex)
                            });
                            // Emit a `WithdrawalProven` event.
                            emit WithdrawalProven(withdrawalHash, _tx.sender, _tx.target);
                        }
                        /**
                         * @notice Finalizes a withdrawal transaction.
                         *
                         * @param _tx Withdrawal transaction to finalize.
                         */
                        function finalizeWithdrawalTransaction(Types.WithdrawalTransaction memory _tx)
                            external
                            whenNotPaused
                        {
                            // Make sure that the l2Sender has not yet been set. The l2Sender is set to a value other
                            // than the default value when a withdrawal transaction is being finalized. This check is
                            // a defacto reentrancy guard.
                            require(
                                l2Sender == Constants.DEFAULT_L2_SENDER,
                                "OptimismPortal: can only trigger one withdrawal per transaction"
                            );
                            // Grab the proven withdrawal from the `provenWithdrawals` map.
                            bytes32 withdrawalHash = Hashing.hashWithdrawal(_tx);
                            ProvenWithdrawal memory provenWithdrawal = provenWithdrawals[withdrawalHash];
                            // A withdrawal can only be finalized if it has been proven. We know that a withdrawal has
                            // been proven at least once when its timestamp is non-zero. Unproven withdrawals will have
                            // a timestamp of zero.
                            require(
                                provenWithdrawal.timestamp != 0,
                                "OptimismPortal: withdrawal has not been proven yet"
                            );
                            // As a sanity check, we make sure that the proven withdrawal's timestamp is greater than
                            // starting timestamp inside the L2OutputOracle. Not strictly necessary but extra layer of
                            // safety against weird bugs in the proving step.
                            require(
                                provenWithdrawal.timestamp >= L2_ORACLE.startingTimestamp(),
                                "OptimismPortal: withdrawal timestamp less than L2 Oracle starting timestamp"
                            );
                            // A proven withdrawal must wait at least the finalization period before it can be
                            // finalized. This waiting period can elapse in parallel with the waiting period for the
                            // output the withdrawal was proven against. In effect, this means that the minimum
                            // withdrawal time is proposal submission time + finalization period.
                            require(
                                _isFinalizationPeriodElapsed(provenWithdrawal.timestamp),
                                "OptimismPortal: proven withdrawal finalization period has not elapsed"
                            );
                            // Grab the OutputProposal from the L2OutputOracle, will revert if the output that
                            // corresponds to the given index has not been proposed yet.
                            Types.OutputProposal memory proposal = L2_ORACLE.getL2Output(
                                provenWithdrawal.l2OutputIndex
                            );
                            // Check that the output root that was used to prove the withdrawal is the same as the
                            // current output root for the given output index. An output root may change if it is
                            // deleted by the challenger address and then re-proposed.
                            require(
                                proposal.outputRoot == provenWithdrawal.outputRoot,
                                "OptimismPortal: output root proven is not the same as current output root"
                            );
                            // Check that the output proposal has also been finalized.
                            require(
                                _isFinalizationPeriodElapsed(proposal.timestamp),
                                "OptimismPortal: output proposal finalization period has not elapsed"
                            );
                            // Check that this withdrawal has not already been finalized, this is replay protection.
                            require(
                                finalizedWithdrawals[withdrawalHash] == false,
                                "OptimismPortal: withdrawal has already been finalized"
                            );
                            // Mark the withdrawal as finalized so it can't be replayed.
                            finalizedWithdrawals[withdrawalHash] = true;
                            // Set the l2Sender so contracts know who triggered this withdrawal on L2.
                            l2Sender = _tx.sender;
                            // Trigger the call to the target contract. We use a custom low level method
                            // SafeCall.callWithMinGas to ensure two key properties
                            //   1. Target contracts cannot force this call to run out of gas by returning a very large
                            //      amount of data (and this is OK because we don't care about the returndata here).
                            //   2. The amount of gas provided to the execution context of the target is at least the
                            //      gas limit specified by the user. If there is not enough gas in the current context
                            //      to accomplish this, `callWithMinGas` will revert.
                            bool success = SafeCall.callWithMinGas(_tx.target, _tx.gasLimit, _tx.value, _tx.data);
                            // Reset the l2Sender back to the default value.
                            l2Sender = Constants.DEFAULT_L2_SENDER;
                            // All withdrawals are immediately finalized. Replayability can
                            // be achieved through contracts built on top of this contract
                            emit WithdrawalFinalized(withdrawalHash, success);
                            // Reverting here is useful for determining the exact gas cost to successfully execute the
                            // sub call to the target contract if the minimum gas limit specified by the user would not
                            // be sufficient to execute the sub call.
                            if (success == false && tx.origin == Constants.ESTIMATION_ADDRESS) {
                                revert("OptimismPortal: withdrawal failed");
                            }
                        }
                        /**
                         * @notice Accepts deposits of ETH and data, and emits a TransactionDeposited event for use in
                         *         deriving deposit transactions. Note that if a deposit is made by a contract, its
                         *         address will be aliased when retrieved using `tx.origin` or `msg.sender`. Consider
                         *         using the CrossDomainMessenger contracts for a simpler developer experience.
                         *
                         * @param _to         Target address on L2.
                         * @param _value      ETH value to send to the recipient.
                         * @param _gasLimit   Minimum L2 gas limit (can be greater than or equal to this value).
                         * @param _isCreation Whether or not the transaction is a contract creation.
                         * @param _data       Data to trigger the recipient with.
                         */
                        function depositTransaction(
                            address _to,
                            uint256 _value,
                            uint64 _gasLimit,
                            bool _isCreation,
                            bytes memory _data
                        ) public payable metered(_gasLimit) {
                            // Just to be safe, make sure that people specify address(0) as the target when doing
                            // contract creations.
                            if (_isCreation) {
                                require(
                                    _to == address(0),
                                    "OptimismPortal: must send to address(0) when creating a contract"
                                );
                            }
                            // Prevent depositing transactions that have too small of a gas limit. Users should pay
                            // more for more resource usage.
                            require(
                                _gasLimit >= minimumGasLimit(uint64(_data.length)),
                                "OptimismPortal: gas limit too small"
                            );
                            // Prevent the creation of deposit transactions that have too much calldata. This gives an
                            // upper limit on the size of unsafe blocks over the p2p network. 120kb is chosen to ensure
                            // that the transaction can fit into the p2p network policy of 128kb even though deposit
                            // transactions are not gossipped over the p2p network.
                            require(_data.length <= 120_000, "OptimismPortal: data too large");
                            // Transform the from-address to its alias if the caller is a contract.
                            address from = msg.sender;
                            if (msg.sender != tx.origin) {
                                from = AddressAliasHelper.applyL1ToL2Alias(msg.sender);
                            }
                            // Compute the opaque data that will be emitted as part of the TransactionDeposited event.
                            // We use opaque data so that we can update the TransactionDeposited event in the future
                            // without breaking the current interface.
                            bytes memory opaqueData = abi.encodePacked(
                                msg.value,
                                _value,
                                _gasLimit,
                                _isCreation,
                                _data
                            );
                            // Emit a TransactionDeposited event so that the rollup node can derive a deposit
                            // transaction for this deposit.
                            emit TransactionDeposited(from, _to, DEPOSIT_VERSION, opaqueData);
                        }
                        /**
                         * @notice Determine if a given output is finalized. Reverts if the call to
                         *         L2_ORACLE.getL2Output reverts. Returns a boolean otherwise.
                         *
                         * @param _l2OutputIndex Index of the L2 output to check.
                         *
                         * @return Whether or not the output is finalized.
                         */
                        function isOutputFinalized(uint256 _l2OutputIndex) external view returns (bool) {
                            return _isFinalizationPeriodElapsed(L2_ORACLE.getL2Output(_l2OutputIndex).timestamp);
                        }
                        /**
                         * @notice Determines whether the finalization period has elapsed w/r/t a given timestamp.
                         *
                         * @param _timestamp Timestamp to check.
                         *
                         * @return Whether or not the finalization period has elapsed.
                         */
                        function _isFinalizationPeriodElapsed(uint256 _timestamp) internal view returns (bool) {
                            return block.timestamp > _timestamp + L2_ORACLE.FINALIZATION_PERIOD_SECONDS();
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    pragma solidity 0.8.15;
                    import { Initializable } from "@openzeppelin/contracts/proxy/utils/Initializable.sol";
                    import { Math } from "@openzeppelin/contracts/utils/math/Math.sol";
                    import { Burn } from "../libraries/Burn.sol";
                    import { Arithmetic } from "../libraries/Arithmetic.sol";
                    /**
                     * @custom:upgradeable
                     * @title ResourceMetering
                     * @notice ResourceMetering implements an EIP-1559 style resource metering system where pricing
                     *         updates automatically based on current demand.
                     */
                    abstract contract ResourceMetering is Initializable {
                        /**
                         * @notice Represents the various parameters that control the way in which resources are
                         *         metered. Corresponds to the EIP-1559 resource metering system.
                         *
                         * @custom:field prevBaseFee   Base fee from the previous block(s).
                         * @custom:field prevBoughtGas Amount of gas bought so far in the current block.
                         * @custom:field prevBlockNum  Last block number that the base fee was updated.
                         */
                        struct ResourceParams {
                            uint128 prevBaseFee;
                            uint64 prevBoughtGas;
                            uint64 prevBlockNum;
                        }
                        /**
                         * @notice Represents the configuration for the EIP-1559 based curve for the deposit gas
                         *         market. These values should be set with care as it is possible to set them in
                         *         a way that breaks the deposit gas market. The target resource limit is defined as
                         *         maxResourceLimit / elasticityMultiplier. This struct was designed to fit within a
                         *         single word. There is additional space for additions in the future.
                         *
                         * @custom:field maxResourceLimit             Represents the maximum amount of deposit gas that
                         *                                            can be purchased per block.
                         * @custom:field elasticityMultiplier         Determines the target resource limit along with
                         *                                            the resource limit.
                         * @custom:field baseFeeMaxChangeDenominator  Determines max change on fee per block.
                         * @custom:field minimumBaseFee               The min deposit base fee, it is clamped to this
                         *                                            value.
                         * @custom:field systemTxMaxGas               The amount of gas supplied to the system
                         *                                            transaction. This should be set to the same number
                         *                                            that the op-node sets as the gas limit for the
                         *                                            system transaction.
                         * @custom:field maximumBaseFee               The max deposit base fee, it is clamped to this
                         *                                            value.
                         */
                        struct ResourceConfig {
                            uint32 maxResourceLimit;
                            uint8 elasticityMultiplier;
                            uint8 baseFeeMaxChangeDenominator;
                            uint32 minimumBaseFee;
                            uint32 systemTxMaxGas;
                            uint128 maximumBaseFee;
                        }
                        /**
                         * @notice EIP-1559 style gas parameters.
                         */
                        ResourceParams public params;
                        /**
                         * @notice Reserve extra slots (to a total of 50) in the storage layout for future upgrades.
                         */
                        uint256[48] private __gap;
                        /**
                         * @notice Meters access to a function based an amount of a requested resource.
                         *
                         * @param _amount Amount of the resource requested.
                         */
                        modifier metered(uint64 _amount) {
                            // Record initial gas amount so we can refund for it later.
                            uint256 initialGas = gasleft();
                            // Run the underlying function.
                            _;
                            // Run the metering function.
                            _metered(_amount, initialGas);
                        }
                        /**
                         * @notice An internal function that holds all of the logic for metering a resource.
                         *
                         * @param _amount     Amount of the resource requested.
                         * @param _initialGas The amount of gas before any modifier execution.
                         */
                        function _metered(uint64 _amount, uint256 _initialGas) internal {
                            // Update block number and base fee if necessary.
                            uint256 blockDiff = block.number - params.prevBlockNum;
                            ResourceConfig memory config = _resourceConfig();
                            int256 targetResourceLimit = int256(uint256(config.maxResourceLimit)) /
                                int256(uint256(config.elasticityMultiplier));
                            if (blockDiff > 0) {
                                // Handle updating EIP-1559 style gas parameters. We use EIP-1559 to restrict the rate
                                // at which deposits can be created and therefore limit the potential for deposits to
                                // spam the L2 system. Fee scheme is very similar to EIP-1559 with minor changes.
                                int256 gasUsedDelta = int256(uint256(params.prevBoughtGas)) - targetResourceLimit;
                                int256 baseFeeDelta = (int256(uint256(params.prevBaseFee)) * gasUsedDelta) /
                                    (targetResourceLimit * int256(uint256(config.baseFeeMaxChangeDenominator)));
                                // Update base fee by adding the base fee delta and clamp the resulting value between
                                // min and max.
                                int256 newBaseFee = Arithmetic.clamp({
                                    _value: int256(uint256(params.prevBaseFee)) + baseFeeDelta,
                                    _min: int256(uint256(config.minimumBaseFee)),
                                    _max: int256(uint256(config.maximumBaseFee))
                                });
                                // If we skipped more than one block, we also need to account for every empty block.
                                // Empty block means there was no demand for deposits in that block, so we should
                                // reflect this lack of demand in the fee.
                                if (blockDiff > 1) {
                                    // Update the base fee by repeatedly applying the exponent 1-(1/change_denominator)
                                    // blockDiff - 1 times. Simulates multiple empty blocks. Clamp the resulting value
                                    // between min and max.
                                    newBaseFee = Arithmetic.clamp({
                                        _value: Arithmetic.cdexp({
                                            _coefficient: newBaseFee,
                                            _denominator: int256(uint256(config.baseFeeMaxChangeDenominator)),
                                            _exponent: int256(blockDiff - 1)
                                        }),
                                        _min: int256(uint256(config.minimumBaseFee)),
                                        _max: int256(uint256(config.maximumBaseFee))
                                    });
                                }
                                // Update new base fee, reset bought gas, and update block number.
                                params.prevBaseFee = uint128(uint256(newBaseFee));
                                params.prevBoughtGas = 0;
                                params.prevBlockNum = uint64(block.number);
                            }
                            // Make sure we can actually buy the resource amount requested by the user.
                            params.prevBoughtGas += _amount;
                            require(
                                int256(uint256(params.prevBoughtGas)) <= int256(uint256(config.maxResourceLimit)),
                                "ResourceMetering: cannot buy more gas than available gas limit"
                            );
                            // Determine the amount of ETH to be paid.
                            uint256 resourceCost = uint256(_amount) * uint256(params.prevBaseFee);
                            // We currently charge for this ETH amount as an L1 gas burn, so we convert the ETH amount
                            // into gas by dividing by the L1 base fee. We assume a minimum base fee of 1 gwei to avoid
                            // division by zero for L1s that don't support 1559 or to avoid excessive gas burns during
                            // periods of extremely low L1 demand. One-day average gas fee hasn't dipped below 1 gwei
                            // during any 1 day period in the last 5 years, so should be fine.
                            uint256 gasCost = resourceCost / Math.max(block.basefee, 1 gwei);
                            // Give the user a refund based on the amount of gas they used to do all of the work up to
                            // this point. Since we're at the end of the modifier, this should be pretty accurate. Acts
                            // effectively like a dynamic stipend (with a minimum value).
                            uint256 usedGas = _initialGas - gasleft();
                            if (gasCost > usedGas) {
                                Burn.gas(gasCost - usedGas);
                            }
                        }
                        /**
                         * @notice Virtual function that returns the resource config. Contracts that inherit this
                         *         contract must implement this function.
                         *
                         * @return ResourceConfig
                         */
                        function _resourceConfig() internal virtual returns (ResourceConfig memory);
                        /**
                         * @notice Sets initial resource parameter values. This function must either be called by the
                         *         initializer function of an upgradeable child contract.
                         */
                        // solhint-disable-next-line func-name-mixedcase
                        function __ResourceMetering_init() internal onlyInitializing {
                            params = ResourceParams({
                                prevBaseFee: 1 gwei,
                                prevBoughtGas: 0,
                                prevBlockNum: uint64(block.number)
                            });
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    pragma solidity 0.8.15;
                    import {
                        OwnableUpgradeable
                    } from "@openzeppelin/contracts-upgradeable/access/OwnableUpgradeable.sol";
                    import { Semver } from "../universal/Semver.sol";
                    import { ResourceMetering } from "./ResourceMetering.sol";
                    /**
                     * @title SystemConfig
                     * @notice The SystemConfig contract is used to manage configuration of an Optimism network. All
                     *         configuration is stored on L1 and picked up by L2 as part of the derviation of the L2
                     *         chain.
                     */
                    contract SystemConfig is OwnableUpgradeable, Semver {
                        /**
                         * @notice Enum representing different types of updates.
                         *
                         * @custom:value BATCHER              Represents an update to the batcher hash.
                         * @custom:value GAS_CONFIG           Represents an update to txn fee config on L2.
                         * @custom:value GAS_LIMIT            Represents an update to gas limit on L2.
                         * @custom:value UNSAFE_BLOCK_SIGNER  Represents an update to the signer key for unsafe
                         *                                    block distrubution.
                         */
                        enum UpdateType {
                            BATCHER,
                            GAS_CONFIG,
                            GAS_LIMIT,
                            UNSAFE_BLOCK_SIGNER
                        }
                        /**
                         * @notice Version identifier, used for upgrades.
                         */
                        uint256 public constant VERSION = 0;
                        /**
                         * @notice Storage slot that the unsafe block signer is stored at. Storing it at this
                         *         deterministic storage slot allows for decoupling the storage layout from the way
                         *         that `solc` lays out storage. The `op-node` uses a storage proof to fetch this value.
                         */
                        bytes32 public constant UNSAFE_BLOCK_SIGNER_SLOT = keccak256("systemconfig.unsafeblocksigner");
                        /**
                         * @notice Fixed L2 gas overhead. Used as part of the L2 fee calculation.
                         */
                        uint256 public overhead;
                        /**
                         * @notice Dynamic L2 gas overhead. Used as part of the L2 fee calculation.
                         */
                        uint256 public scalar;
                        /**
                         * @notice Identifier for the batcher. For version 1 of this configuration, this is represented
                         *         as an address left-padded with zeros to 32 bytes.
                         */
                        bytes32 public batcherHash;
                        /**
                         * @notice L2 block gas limit.
                         */
                        uint64 public gasLimit;
                        /**
                         * @notice The configuration for the deposit fee market. Used by the OptimismPortal
                         *         to meter the cost of buying L2 gas on L1. Set as internal and wrapped with a getter
                         *         so that the struct is returned instead of a tuple.
                         */
                        ResourceMetering.ResourceConfig internal _resourceConfig;
                        /**
                         * @notice Emitted when configuration is updated
                         *
                         * @param version    SystemConfig version.
                         * @param updateType Type of update.
                         * @param data       Encoded update data.
                         */
                        event ConfigUpdate(uint256 indexed version, UpdateType indexed updateType, bytes data);
                        /**
                         * @custom:semver 1.3.0
                         *
                         * @param _owner             Initial owner of the contract.
                         * @param _overhead          Initial overhead value.
                         * @param _scalar            Initial scalar value.
                         * @param _batcherHash       Initial batcher hash.
                         * @param _gasLimit          Initial gas limit.
                         * @param _unsafeBlockSigner Initial unsafe block signer address.
                         * @param _config            Initial resource config.
                         */
                        constructor(
                            address _owner,
                            uint256 _overhead,
                            uint256 _scalar,
                            bytes32 _batcherHash,
                            uint64 _gasLimit,
                            address _unsafeBlockSigner,
                            ResourceMetering.ResourceConfig memory _config
                        ) Semver(1, 3, 0) {
                            initialize({
                                _owner: _owner,
                                _overhead: _overhead,
                                _scalar: _scalar,
                                _batcherHash: _batcherHash,
                                _gasLimit: _gasLimit,
                                _unsafeBlockSigner: _unsafeBlockSigner,
                                _config: _config
                            });
                        }
                        /**
                         * @notice Initializer. The resource config must be set before the
                         *         require check.
                         *
                         * @param _owner             Initial owner of the contract.
                         * @param _overhead          Initial overhead value.
                         * @param _scalar            Initial scalar value.
                         * @param _batcherHash       Initial batcher hash.
                         * @param _gasLimit          Initial gas limit.
                         * @param _unsafeBlockSigner Initial unsafe block signer address.
                         * @param _config            Initial ResourceConfig.
                         */
                        function initialize(
                            address _owner,
                            uint256 _overhead,
                            uint256 _scalar,
                            bytes32 _batcherHash,
                            uint64 _gasLimit,
                            address _unsafeBlockSigner,
                            ResourceMetering.ResourceConfig memory _config
                        ) public initializer {
                            __Ownable_init();
                            transferOwnership(_owner);
                            overhead = _overhead;
                            scalar = _scalar;
                            batcherHash = _batcherHash;
                            gasLimit = _gasLimit;
                            _setUnsafeBlockSigner(_unsafeBlockSigner);
                            _setResourceConfig(_config);
                            require(_gasLimit >= minimumGasLimit(), "SystemConfig: gas limit too low");
                        }
                        /**
                         * @notice Returns the minimum L2 gas limit that can be safely set for the system to
                         *         operate. The L2 gas limit must be larger than or equal to the amount of
                         *         gas that is allocated for deposits per block plus the amount of gas that
                         *         is allocated for the system transaction.
                         *         This function is used to determine if changes to parameters are safe.
                         *
                         * @return uint64
                         */
                        function minimumGasLimit() public view returns (uint64) {
                            return uint64(_resourceConfig.maxResourceLimit) + uint64(_resourceConfig.systemTxMaxGas);
                        }
                        /**
                         * @notice High level getter for the unsafe block signer address. Unsafe blocks can be
                         *         propagated across the p2p network if they are signed by the key corresponding to
                         *         this address.
                         *
                         * @return Address of the unsafe block signer.
                         */
                        // solhint-disable-next-line ordering
                        function unsafeBlockSigner() external view returns (address) {
                            address addr;
                            bytes32 slot = UNSAFE_BLOCK_SIGNER_SLOT;
                            assembly {
                                addr := sload(slot)
                            }
                            return addr;
                        }
                        /**
                         * @notice Updates the unsafe block signer address.
                         *
                         * @param _unsafeBlockSigner New unsafe block signer address.
                         */
                        function setUnsafeBlockSigner(address _unsafeBlockSigner) external onlyOwner {
                            _setUnsafeBlockSigner(_unsafeBlockSigner);
                            bytes memory data = abi.encode(_unsafeBlockSigner);
                            emit ConfigUpdate(VERSION, UpdateType.UNSAFE_BLOCK_SIGNER, data);
                        }
                        /**
                         * @notice Updates the batcher hash.
                         *
                         * @param _batcherHash New batcher hash.
                         */
                        function setBatcherHash(bytes32 _batcherHash) external onlyOwner {
                            batcherHash = _batcherHash;
                            bytes memory data = abi.encode(_batcherHash);
                            emit ConfigUpdate(VERSION, UpdateType.BATCHER, data);
                        }
                        /**
                         * @notice Updates gas config.
                         *
                         * @param _overhead New overhead value.
                         * @param _scalar   New scalar value.
                         */
                        function setGasConfig(uint256 _overhead, uint256 _scalar) external onlyOwner {
                            overhead = _overhead;
                            scalar = _scalar;
                            bytes memory data = abi.encode(_overhead, _scalar);
                            emit ConfigUpdate(VERSION, UpdateType.GAS_CONFIG, data);
                        }
                        /**
                         * @notice Updates the L2 gas limit.
                         *
                         * @param _gasLimit New gas limit.
                         */
                        function setGasLimit(uint64 _gasLimit) external onlyOwner {
                            require(_gasLimit >= minimumGasLimit(), "SystemConfig: gas limit too low");
                            gasLimit = _gasLimit;
                            bytes memory data = abi.encode(_gasLimit);
                            emit ConfigUpdate(VERSION, UpdateType.GAS_LIMIT, data);
                        }
                        /**
                         * @notice Low level setter for the unsafe block signer address. This function exists to
                         *         deduplicate code around storing the unsafeBlockSigner address in storage.
                         *
                         * @param _unsafeBlockSigner New unsafeBlockSigner value.
                         */
                        function _setUnsafeBlockSigner(address _unsafeBlockSigner) internal {
                            bytes32 slot = UNSAFE_BLOCK_SIGNER_SLOT;
                            assembly {
                                sstore(slot, _unsafeBlockSigner)
                            }
                        }
                        /**
                         * @notice A getter for the resource config. Ensures that the struct is
                         *         returned instead of a tuple.
                         *
                         * @return ResourceConfig
                         */
                        function resourceConfig() external view returns (ResourceMetering.ResourceConfig memory) {
                            return _resourceConfig;
                        }
                        /**
                         * @notice An external setter for the resource config. In the future, this
                         *         method may emit an event that the `op-node` picks up for when the
                         *         resource config is changed.
                         *
                         * @param _config The new resource config values.
                         */
                        function setResourceConfig(ResourceMetering.ResourceConfig memory _config) external onlyOwner {
                            _setResourceConfig(_config);
                        }
                        /**
                         * @notice An internal setter for the resource config. Ensures that the
                         *         config is sane before storing it by checking for invariants.
                         *
                         * @param _config The new resource config.
                         */
                        function _setResourceConfig(ResourceMetering.ResourceConfig memory _config) internal {
                            // Min base fee must be less than or equal to max base fee.
                            require(
                                _config.minimumBaseFee <= _config.maximumBaseFee,
                                "SystemConfig: min base fee must be less than max base"
                            );
                            // Base fee change denominator must be greater than 1.
                            require(
                                _config.baseFeeMaxChangeDenominator > 1,
                                "SystemConfig: denominator must be larger than 1"
                            );
                            // Max resource limit plus system tx gas must be less than or equal to the L2 gas limit.
                            // The gas limit must be increased before these values can be increased.
                            require(
                                _config.maxResourceLimit + _config.systemTxMaxGas <= gasLimit,
                                "SystemConfig: gas limit too low"
                            );
                            // Elasticity multiplier must be greater than 0.
                            require(
                                _config.elasticityMultiplier > 0,
                                "SystemConfig: elasticity multiplier cannot be 0"
                            );
                            // No precision loss when computing target resource limit.
                            require(
                                ((_config.maxResourceLimit / _config.elasticityMultiplier) *
                                    _config.elasticityMultiplier) == _config.maxResourceLimit,
                                "SystemConfig: precision loss with target resource limit"
                            );
                            _resourceConfig = _config;
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    pragma solidity 0.8.15;
                    import { SignedMath } from "@openzeppelin/contracts/utils/math/SignedMath.sol";
                    import { FixedPointMathLib } from "@rari-capital/solmate/src/utils/FixedPointMathLib.sol";
                    /**
                     * @title Arithmetic
                     * @notice Even more math than before.
                     */
                    library Arithmetic {
                        /**
                         * @notice Clamps a value between a minimum and maximum.
                         *
                         * @param _value The value to clamp.
                         * @param _min   The minimum value.
                         * @param _max   The maximum value.
                         *
                         * @return The clamped value.
                         */
                        function clamp(
                            int256 _value,
                            int256 _min,
                            int256 _max
                        ) internal pure returns (int256) {
                            return SignedMath.min(SignedMath.max(_value, _min), _max);
                        }
                        /**
                         * @notice (c)oefficient (d)enominator (exp)onentiation function.
                         *         Returns the result of: c * (1 - 1/d)^exp.
                         *
                         * @param _coefficient Coefficient of the function.
                         * @param _denominator Fractional denominator.
                         * @param _exponent    Power function exponent.
                         *
                         * @return Result of c * (1 - 1/d)^exp.
                         */
                        function cdexp(
                            int256 _coefficient,
                            int256 _denominator,
                            int256 _exponent
                        ) internal pure returns (int256) {
                            return
                                (_coefficient *
                                    (FixedPointMathLib.powWad(1e18 - (1e18 / _denominator), _exponent * 1e18))) / 1e18;
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    pragma solidity 0.8.15;
                    /**
                     * @title Burn
                     * @notice Utilities for burning stuff.
                     */
                    library Burn {
                        /**
                         * Burns a given amount of ETH.
                         *
                         * @param _amount Amount of ETH to burn.
                         */
                        function eth(uint256 _amount) internal {
                            new Burner{ value: _amount }();
                        }
                        /**
                         * Burns a given amount of gas.
                         *
                         * @param _amount Amount of gas to burn.
                         */
                        function gas(uint256 _amount) internal view {
                            uint256 i = 0;
                            uint256 initialGas = gasleft();
                            while (initialGas - gasleft() < _amount) {
                                ++i;
                            }
                        }
                    }
                    /**
                     * @title Burner
                     * @notice Burner self-destructs on creation and sends all ETH to itself, removing all ETH given to
                     *         the contract from the circulating supply. Self-destructing is the only way to remove ETH
                     *         from the circulating supply.
                     */
                    contract Burner {
                        constructor() payable {
                            selfdestruct(payable(address(this)));
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    pragma solidity ^0.8.0;
                    /**
                     * @title Bytes
                     * @notice Bytes is a library for manipulating byte arrays.
                     */
                    library Bytes {
                        /**
                         * @custom:attribution https://github.com/GNSPS/solidity-bytes-utils
                         * @notice Slices a byte array with a given starting index and length. Returns a new byte array
                         *         as opposed to a pointer to the original array. Will throw if trying to slice more
                         *         bytes than exist in the array.
                         *
                         * @param _bytes Byte array to slice.
                         * @param _start Starting index of the slice.
                         * @param _length Length of the slice.
                         *
                         * @return Slice of the input byte array.
                         */
                        function slice(
                            bytes memory _bytes,
                            uint256 _start,
                            uint256 _length
                        ) internal pure returns (bytes memory) {
                            unchecked {
                                require(_length + 31 >= _length, "slice_overflow");
                                require(_start + _length >= _start, "slice_overflow");
                                require(_bytes.length >= _start + _length, "slice_outOfBounds");
                            }
                            bytes memory tempBytes;
                            assembly {
                                switch iszero(_length)
                                case 0 {
                                    // Get a location of some free memory and store it in tempBytes as
                                    // Solidity does for memory variables.
                                    tempBytes := mload(0x40)
                                    // The first word of the slice result is potentially a partial
                                    // word read from the original array. To read it, we calculate
                                    // the length of that partial word and start copying that many
                                    // bytes into the array. The first word we copy will start with
                                    // data we don't care about, but the last `lengthmod` bytes will
                                    // land at the beginning of the contents of the new array. When
                                    // we're done copying, we overwrite the full first word with
                                    // the actual length of the slice.
                                    let lengthmod := and(_length, 31)
                                    // The multiplication in the next line is necessary
                                    // because when slicing multiples of 32 bytes (lengthmod == 0)
                                    // the following copy loop was copying the origin's length
                                    // and then ending prematurely not copying everything it should.
                                    let mc := add(add(tempBytes, lengthmod), mul(0x20, iszero(lengthmod)))
                                    let end := add(mc, _length)
                                    for {
                                        // The multiplication in the next line has the same exact purpose
                                        // as the one above.
                                        let cc := add(add(add(_bytes, lengthmod), mul(0x20, iszero(lengthmod))), _start)
                                    } lt(mc, end) {
                                        mc := add(mc, 0x20)
                                        cc := add(cc, 0x20)
                                    } {
                                        mstore(mc, mload(cc))
                                    }
                                    mstore(tempBytes, _length)
                                    //update free-memory pointer
                                    //allocating the array padded to 32 bytes like the compiler does now
                                    mstore(0x40, and(add(mc, 31), not(31)))
                                }
                                //if we want a zero-length slice let's just return a zero-length array
                                default {
                                    tempBytes := mload(0x40)
                                    //zero out the 32 bytes slice we are about to return
                                    //we need to do it because Solidity does not garbage collect
                                    mstore(tempBytes, 0)
                                    mstore(0x40, add(tempBytes, 0x20))
                                }
                            }
                            return tempBytes;
                        }
                        /**
                         * @notice Slices a byte array with a given starting index up to the end of the original byte
                         *         array. Returns a new array rathern than a pointer to the original.
                         *
                         * @param _bytes Byte array to slice.
                         * @param _start Starting index of the slice.
                         *
                         * @return Slice of the input byte array.
                         */
                        function slice(bytes memory _bytes, uint256 _start) internal pure returns (bytes memory) {
                            if (_start >= _bytes.length) {
                                return bytes("");
                            }
                            return slice(_bytes, _start, _bytes.length - _start);
                        }
                        /**
                         * @notice Converts a byte array into a nibble array by splitting each byte into two nibbles.
                         *         Resulting nibble array will be exactly twice as long as the input byte array.
                         *
                         * @param _bytes Input byte array to convert.
                         *
                         * @return Resulting nibble array.
                         */
                        function toNibbles(bytes memory _bytes) internal pure returns (bytes memory) {
                            uint256 bytesLength = _bytes.length;
                            bytes memory nibbles = new bytes(bytesLength * 2);
                            bytes1 b;
                            for (uint256 i = 0; i < bytesLength; ) {
                                b = _bytes[i];
                                nibbles[i * 2] = b >> 4;
                                nibbles[i * 2 + 1] = b & 0x0f;
                                unchecked {
                                    ++i;
                                }
                            }
                            return nibbles;
                        }
                        /**
                         * @notice Compares two byte arrays by comparing their keccak256 hashes.
                         *
                         * @param _bytes First byte array to compare.
                         * @param _other Second byte array to compare.
                         *
                         * @return True if the two byte arrays are equal, false otherwise.
                         */
                        function equal(bytes memory _bytes, bytes memory _other) internal pure returns (bool) {
                            return keccak256(_bytes) == keccak256(_other);
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    pragma solidity ^0.8.0;
                    import { ResourceMetering } from "../L1/ResourceMetering.sol";
                    /**
                     * @title Constants
                     * @notice Constants is a library for storing constants. Simple! Don't put everything in here, just
                     *         the stuff used in multiple contracts. Constants that only apply to a single contract
                     *         should be defined in that contract instead.
                     */
                    library Constants {
                        /**
                         * @notice Special address to be used as the tx origin for gas estimation calls in the
                         *         OptimismPortal and CrossDomainMessenger calls. You only need to use this address if
                         *         the minimum gas limit specified by the user is not actually enough to execute the
                         *         given message and you're attempting to estimate the actual necessary gas limit. We
                         *         use address(1) because it's the ecrecover precompile and therefore guaranteed to
                         *         never have any code on any EVM chain.
                         */
                        address internal constant ESTIMATION_ADDRESS = address(1);
                        /**
                         * @notice Value used for the L2 sender storage slot in both the OptimismPortal and the
                         *         CrossDomainMessenger contracts before an actual sender is set. This value is
                         *         non-zero to reduce the gas cost of message passing transactions.
                         */
                        address internal constant DEFAULT_L2_SENDER = 0x000000000000000000000000000000000000dEaD;
                        /**
                         * @notice Returns the default values for the ResourceConfig. These are the recommended values
                         *         for a production network.
                         */
                        function DEFAULT_RESOURCE_CONFIG()
                            internal
                            pure
                            returns (ResourceMetering.ResourceConfig memory)
                        {
                            ResourceMetering.ResourceConfig memory config = ResourceMetering.ResourceConfig({
                                maxResourceLimit: 20_000_000,
                                elasticityMultiplier: 10,
                                baseFeeMaxChangeDenominator: 8,
                                minimumBaseFee: 1 gwei,
                                systemTxMaxGas: 1_000_000,
                                maximumBaseFee: type(uint128).max
                            });
                            return config;
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    pragma solidity ^0.8.0;
                    import { Types } from "./Types.sol";
                    import { Hashing } from "./Hashing.sol";
                    import { RLPWriter } from "./rlp/RLPWriter.sol";
                    /**
                     * @title Encoding
                     * @notice Encoding handles Optimism's various different encoding schemes.
                     */
                    library Encoding {
                        /**
                         * @notice RLP encodes the L2 transaction that would be generated when a given deposit is sent
                         *         to the L2 system. Useful for searching for a deposit in the L2 system. The
                         *         transaction is prefixed with 0x7e to identify its EIP-2718 type.
                         *
                         * @param _tx User deposit transaction to encode.
                         *
                         * @return RLP encoded L2 deposit transaction.
                         */
                        function encodeDepositTransaction(Types.UserDepositTransaction memory _tx)
                            internal
                            pure
                            returns (bytes memory)
                        {
                            bytes32 source = Hashing.hashDepositSource(_tx.l1BlockHash, _tx.logIndex);
                            bytes[] memory raw = new bytes[](8);
                            raw[0] = RLPWriter.writeBytes(abi.encodePacked(source));
                            raw[1] = RLPWriter.writeAddress(_tx.from);
                            raw[2] = _tx.isCreation ? RLPWriter.writeBytes("") : RLPWriter.writeAddress(_tx.to);
                            raw[3] = RLPWriter.writeUint(_tx.mint);
                            raw[4] = RLPWriter.writeUint(_tx.value);
                            raw[5] = RLPWriter.writeUint(uint256(_tx.gasLimit));
                            raw[6] = RLPWriter.writeBool(false);
                            raw[7] = RLPWriter.writeBytes(_tx.data);
                            return abi.encodePacked(uint8(0x7e), RLPWriter.writeList(raw));
                        }
                        /**
                         * @notice Encodes the cross domain message based on the version that is encoded into the
                         *         message nonce.
                         *
                         * @param _nonce    Message nonce with version encoded into the first two bytes.
                         * @param _sender   Address of the sender of the message.
                         * @param _target   Address of the target of the message.
                         * @param _value    ETH value to send to the target.
                         * @param _gasLimit Gas limit to use for the message.
                         * @param _data     Data to send with the message.
                         *
                         * @return Encoded cross domain message.
                         */
                        function encodeCrossDomainMessage(
                            uint256 _nonce,
                            address _sender,
                            address _target,
                            uint256 _value,
                            uint256 _gasLimit,
                            bytes memory _data
                        ) internal pure returns (bytes memory) {
                            (, uint16 version) = decodeVersionedNonce(_nonce);
                            if (version == 0) {
                                return encodeCrossDomainMessageV0(_target, _sender, _data, _nonce);
                            } else if (version == 1) {
                                return encodeCrossDomainMessageV1(_nonce, _sender, _target, _value, _gasLimit, _data);
                            } else {
                                revert("Encoding: unknown cross domain message version");
                            }
                        }
                        /**
                         * @notice Encodes a cross domain message based on the V0 (legacy) encoding.
                         *
                         * @param _target Address of the target of the message.
                         * @param _sender Address of the sender of the message.
                         * @param _data   Data to send with the message.
                         * @param _nonce  Message nonce.
                         *
                         * @return Encoded cross domain message.
                         */
                        function encodeCrossDomainMessageV0(
                            address _target,
                            address _sender,
                            bytes memory _data,
                            uint256 _nonce
                        ) internal pure returns (bytes memory) {
                            return
                                abi.encodeWithSignature(
                                    "relayMessage(address,address,bytes,uint256)",
                                    _target,
                                    _sender,
                                    _data,
                                    _nonce
                                );
                        }
                        /**
                         * @notice Encodes a cross domain message based on the V1 (current) encoding.
                         *
                         * @param _nonce    Message nonce.
                         * @param _sender   Address of the sender of the message.
                         * @param _target   Address of the target of the message.
                         * @param _value    ETH value to send to the target.
                         * @param _gasLimit Gas limit to use for the message.
                         * @param _data     Data to send with the message.
                         *
                         * @return Encoded cross domain message.
                         */
                        function encodeCrossDomainMessageV1(
                            uint256 _nonce,
                            address _sender,
                            address _target,
                            uint256 _value,
                            uint256 _gasLimit,
                            bytes memory _data
                        ) internal pure returns (bytes memory) {
                            return
                                abi.encodeWithSignature(
                                    "relayMessage(uint256,address,address,uint256,uint256,bytes)",
                                    _nonce,
                                    _sender,
                                    _target,
                                    _value,
                                    _gasLimit,
                                    _data
                                );
                        }
                        /**
                         * @notice Adds a version number into the first two bytes of a message nonce.
                         *
                         * @param _nonce   Message nonce to encode into.
                         * @param _version Version number to encode into the message nonce.
                         *
                         * @return Message nonce with version encoded into the first two bytes.
                         */
                        function encodeVersionedNonce(uint240 _nonce, uint16 _version) internal pure returns (uint256) {
                            uint256 nonce;
                            assembly {
                                nonce := or(shl(240, _version), _nonce)
                            }
                            return nonce;
                        }
                        /**
                         * @notice Pulls the version out of a version-encoded nonce.
                         *
                         * @param _nonce Message nonce with version encoded into the first two bytes.
                         *
                         * @return Nonce without encoded version.
                         * @return Version of the message.
                         */
                        function decodeVersionedNonce(uint256 _nonce) internal pure returns (uint240, uint16) {
                            uint240 nonce;
                            uint16 version;
                            assembly {
                                nonce := and(_nonce, 0x0000ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff)
                                version := shr(240, _nonce)
                            }
                            return (nonce, version);
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    pragma solidity ^0.8.0;
                    import { Types } from "./Types.sol";
                    import { Encoding } from "./Encoding.sol";
                    /**
                     * @title Hashing
                     * @notice Hashing handles Optimism's various different hashing schemes.
                     */
                    library Hashing {
                        /**
                         * @notice Computes the hash of the RLP encoded L2 transaction that would be generated when a
                         *         given deposit is sent to the L2 system. Useful for searching for a deposit in the L2
                         *         system.
                         *
                         * @param _tx User deposit transaction to hash.
                         *
                         * @return Hash of the RLP encoded L2 deposit transaction.
                         */
                        function hashDepositTransaction(Types.UserDepositTransaction memory _tx)
                            internal
                            pure
                            returns (bytes32)
                        {
                            return keccak256(Encoding.encodeDepositTransaction(_tx));
                        }
                        /**
                         * @notice Computes the deposit transaction's "source hash", a value that guarantees the hash
                         *         of the L2 transaction that corresponds to a deposit is unique and is
                         *         deterministically generated from L1 transaction data.
                         *
                         * @param _l1BlockHash Hash of the L1 block where the deposit was included.
                         * @param _logIndex    The index of the log that created the deposit transaction.
                         *
                         * @return Hash of the deposit transaction's "source hash".
                         */
                        function hashDepositSource(bytes32 _l1BlockHash, uint256 _logIndex)
                            internal
                            pure
                            returns (bytes32)
                        {
                            bytes32 depositId = keccak256(abi.encode(_l1BlockHash, _logIndex));
                            return keccak256(abi.encode(bytes32(0), depositId));
                        }
                        /**
                         * @notice Hashes the cross domain message based on the version that is encoded into the
                         *         message nonce.
                         *
                         * @param _nonce    Message nonce with version encoded into the first two bytes.
                         * @param _sender   Address of the sender of the message.
                         * @param _target   Address of the target of the message.
                         * @param _value    ETH value to send to the target.
                         * @param _gasLimit Gas limit to use for the message.
                         * @param _data     Data to send with the message.
                         *
                         * @return Hashed cross domain message.
                         */
                        function hashCrossDomainMessage(
                            uint256 _nonce,
                            address _sender,
                            address _target,
                            uint256 _value,
                            uint256 _gasLimit,
                            bytes memory _data
                        ) internal pure returns (bytes32) {
                            (, uint16 version) = Encoding.decodeVersionedNonce(_nonce);
                            if (version == 0) {
                                return hashCrossDomainMessageV0(_target, _sender, _data, _nonce);
                            } else if (version == 1) {
                                return hashCrossDomainMessageV1(_nonce, _sender, _target, _value, _gasLimit, _data);
                            } else {
                                revert("Hashing: unknown cross domain message version");
                            }
                        }
                        /**
                         * @notice Hashes a cross domain message based on the V0 (legacy) encoding.
                         *
                         * @param _target Address of the target of the message.
                         * @param _sender Address of the sender of the message.
                         * @param _data   Data to send with the message.
                         * @param _nonce  Message nonce.
                         *
                         * @return Hashed cross domain message.
                         */
                        function hashCrossDomainMessageV0(
                            address _target,
                            address _sender,
                            bytes memory _data,
                            uint256 _nonce
                        ) internal pure returns (bytes32) {
                            return keccak256(Encoding.encodeCrossDomainMessageV0(_target, _sender, _data, _nonce));
                        }
                        /**
                         * @notice Hashes a cross domain message based on the V1 (current) encoding.
                         *
                         * @param _nonce    Message nonce.
                         * @param _sender   Address of the sender of the message.
                         * @param _target   Address of the target of the message.
                         * @param _value    ETH value to send to the target.
                         * @param _gasLimit Gas limit to use for the message.
                         * @param _data     Data to send with the message.
                         *
                         * @return Hashed cross domain message.
                         */
                        function hashCrossDomainMessageV1(
                            uint256 _nonce,
                            address _sender,
                            address _target,
                            uint256 _value,
                            uint256 _gasLimit,
                            bytes memory _data
                        ) internal pure returns (bytes32) {
                            return
                                keccak256(
                                    Encoding.encodeCrossDomainMessageV1(
                                        _nonce,
                                        _sender,
                                        _target,
                                        _value,
                                        _gasLimit,
                                        _data
                                    )
                                );
                        }
                        /**
                         * @notice Derives the withdrawal hash according to the encoding in the L2 Withdrawer contract
                         *
                         * @param _tx Withdrawal transaction to hash.
                         *
                         * @return Hashed withdrawal transaction.
                         */
                        function hashWithdrawal(Types.WithdrawalTransaction memory _tx)
                            internal
                            pure
                            returns (bytes32)
                        {
                            return
                                keccak256(
                                    abi.encode(_tx.nonce, _tx.sender, _tx.target, _tx.value, _tx.gasLimit, _tx.data)
                                );
                        }
                        /**
                         * @notice Hashes the various elements of an output root proof into an output root hash which
                         *         can be used to check if the proof is valid.
                         *
                         * @param _outputRootProof Output root proof which should hash to an output root.
                         *
                         * @return Hashed output root proof.
                         */
                        function hashOutputRootProof(Types.OutputRootProof memory _outputRootProof)
                            internal
                            pure
                            returns (bytes32)
                        {
                            return
                                keccak256(
                                    abi.encode(
                                        _outputRootProof.version,
                                        _outputRootProof.stateRoot,
                                        _outputRootProof.messagePasserStorageRoot,
                                        _outputRootProof.latestBlockhash
                                    )
                                );
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    pragma solidity ^0.8.0;
                    /**
                     * @title Predeploys
                     * @notice Contains constant addresses for contracts that are pre-deployed to the L2 system.
                     */
                    library Predeploys {
                        /**
                         * @notice Address of the L2ToL1MessagePasser predeploy.
                         */
                        address internal constant L2_TO_L1_MESSAGE_PASSER = 0x4200000000000000000000000000000000000016;
                        /**
                         * @notice Address of the L2CrossDomainMessenger predeploy.
                         */
                        address internal constant L2_CROSS_DOMAIN_MESSENGER =
                            0x4200000000000000000000000000000000000007;
                        /**
                         * @notice Address of the L2StandardBridge predeploy.
                         */
                        address internal constant L2_STANDARD_BRIDGE = 0x4200000000000000000000000000000000000010;
                        /**
                         * @notice Address of the L2ERC721Bridge predeploy.
                         */
                        address internal constant L2_ERC721_BRIDGE = 0x4200000000000000000000000000000000000014;
                        /**
                         * @notice Address of the SequencerFeeWallet predeploy.
                         */
                        address internal constant SEQUENCER_FEE_WALLET = 0x4200000000000000000000000000000000000011;
                        /**
                         * @notice Address of the OptimismMintableERC20Factory predeploy.
                         */
                        address internal constant OPTIMISM_MINTABLE_ERC20_FACTORY =
                            0x4200000000000000000000000000000000000012;
                        /**
                         * @notice Address of the OptimismMintableERC721Factory predeploy.
                         */
                        address internal constant OPTIMISM_MINTABLE_ERC721_FACTORY =
                            0x4200000000000000000000000000000000000017;
                        /**
                         * @notice Address of the L1Block predeploy.
                         */
                        address internal constant L1_BLOCK_ATTRIBUTES = 0x4200000000000000000000000000000000000015;
                        /**
                         * @notice Address of the GasPriceOracle predeploy. Includes fee information
                         *         and helpers for computing the L1 portion of the transaction fee.
                         */
                        address internal constant GAS_PRICE_ORACLE = 0x420000000000000000000000000000000000000F;
                        /**
                         * @custom:legacy
                         * @notice Address of the L1MessageSender predeploy. Deprecated. Use L2CrossDomainMessenger
                         *         or access tx.origin (or msg.sender) in a L1 to L2 transaction instead.
                         */
                        address internal constant L1_MESSAGE_SENDER = 0x4200000000000000000000000000000000000001;
                        /**
                         * @custom:legacy
                         * @notice Address of the DeployerWhitelist predeploy. No longer active.
                         */
                        address internal constant DEPLOYER_WHITELIST = 0x4200000000000000000000000000000000000002;
                        /**
                         * @custom:legacy
                         * @notice Address of the LegacyERC20ETH predeploy. Deprecated. Balances are migrated to the
                         *         state trie as of the Bedrock upgrade. Contract has been locked and write functions
                         *         can no longer be accessed.
                         */
                        address internal constant LEGACY_ERC20_ETH = 0xDeadDeAddeAddEAddeadDEaDDEAdDeaDDeAD0000;
                        /**
                         * @custom:legacy
                         * @notice Address of the L1BlockNumber predeploy. Deprecated. Use the L1Block predeploy
                         *         instead, which exposes more information about the L1 state.
                         */
                        address internal constant L1_BLOCK_NUMBER = 0x4200000000000000000000000000000000000013;
                        /**
                         * @custom:legacy
                         * @notice Address of the LegacyMessagePasser predeploy. Deprecate. Use the updated
                         *         L2ToL1MessagePasser contract instead.
                         */
                        address internal constant LEGACY_MESSAGE_PASSER = 0x4200000000000000000000000000000000000000;
                        /**
                         * @notice Address of the ProxyAdmin predeploy.
                         */
                        address internal constant PROXY_ADMIN = 0x4200000000000000000000000000000000000018;
                        /**
                         * @notice Address of the BaseFeeVault predeploy.
                         */
                        address internal constant BASE_FEE_VAULT = 0x4200000000000000000000000000000000000019;
                        /**
                         * @notice Address of the L1FeeVault predeploy.
                         */
                        address internal constant L1_FEE_VAULT = 0x420000000000000000000000000000000000001A;
                        /**
                         * @notice Address of the GovernanceToken predeploy.
                         */
                        address internal constant GOVERNANCE_TOKEN = 0x4200000000000000000000000000000000000042;
                    }
                    // SPDX-License-Identifier: MIT
                    pragma solidity 0.8.15;
                    /**
                     * @title SafeCall
                     * @notice Perform low level safe calls
                     */
                    library SafeCall {
                        /**
                         * @notice Performs a low level call without copying any returndata.
                         * @dev Passes no calldata to the call context.
                         *
                         * @param _target   Address to call
                         * @param _gas      Amount of gas to pass to the call
                         * @param _value    Amount of value to pass to the call
                         */
                        function send(
                            address _target,
                            uint256 _gas,
                            uint256 _value
                        ) internal returns (bool) {
                            bool _success;
                            assembly {
                                _success := call(
                                    _gas, // gas
                                    _target, // recipient
                                    _value, // ether value
                                    0, // inloc
                                    0, // inlen
                                    0, // outloc
                                    0 // outlen
                                )
                            }
                            return _success;
                        }
                        /**
                         * @notice Perform a low level call without copying any returndata
                         *
                         * @param _target   Address to call
                         * @param _gas      Amount of gas to pass to the call
                         * @param _value    Amount of value to pass to the call
                         * @param _calldata Calldata to pass to the call
                         */
                        function call(
                            address _target,
                            uint256 _gas,
                            uint256 _value,
                            bytes memory _calldata
                        ) internal returns (bool) {
                            bool _success;
                            assembly {
                                _success := call(
                                    _gas, // gas
                                    _target, // recipient
                                    _value, // ether value
                                    add(_calldata, 32), // inloc
                                    mload(_calldata), // inlen
                                    0, // outloc
                                    0 // outlen
                                )
                            }
                            return _success;
                        }
                        /**
                         * @notice Helper function to determine if there is sufficient gas remaining within the context
                         *         to guarantee that the minimum gas requirement for a call will be met as well as
                         *         optionally reserving a specified amount of gas for after the call has concluded.
                         * @param _minGas      The minimum amount of gas that may be passed to the target context.
                         * @param _reservedGas Optional amount of gas to reserve for the caller after the execution
                         *                     of the target context.
                         * @return `true` if there is enough gas remaining to safely supply `_minGas` to the target
                         *         context as well as reserve `_reservedGas` for the caller after the execution of
                         *         the target context.
                         * @dev !!!!! FOOTGUN ALERT !!!!!
                         *      1.) The 40_000 base buffer is to account for the worst case of the dynamic cost of the
                         *          `CALL` opcode's `address_access_cost`, `positive_value_cost`, and
                         *          `value_to_empty_account_cost` factors with an added buffer of 5,700 gas. It is
                         *          still possible to self-rekt by initiating a withdrawal with a minimum gas limit
                         *          that does not account for the `memory_expansion_cost` & `code_execution_cost`
                         *          factors of the dynamic cost of the `CALL` opcode.
                         *      2.) This function should *directly* precede the external call if possible. There is an
                         *          added buffer to account for gas consumed between this check and the call, but it
                         *          is only 5,700 gas.
                         *      3.) Because EIP-150 ensures that a maximum of 63/64ths of the remaining gas in the call
                         *          frame may be passed to a subcontext, we need to ensure that the gas will not be
                         *          truncated.
                         *      4.) Use wisely. This function is not a silver bullet.
                         */
                        function hasMinGas(uint256 _minGas, uint256 _reservedGas) internal view returns (bool) {
                            bool _hasMinGas;
                            assembly {
                                // Equation: gas × 63 ≥ minGas × 64 + 63(40_000 + reservedGas)
                                _hasMinGas := iszero(
                                    lt(mul(gas(), 63), add(mul(_minGas, 64), mul(add(40000, _reservedGas), 63)))
                                )
                            }
                            return _hasMinGas;
                        }
                        /**
                         * @notice Perform a low level call without copying any returndata. This function
                         *         will revert if the call cannot be performed with the specified minimum
                         *         gas.
                         *
                         * @param _target   Address to call
                         * @param _minGas   The minimum amount of gas that may be passed to the call
                         * @param _value    Amount of value to pass to the call
                         * @param _calldata Calldata to pass to the call
                         */
                        function callWithMinGas(
                            address _target,
                            uint256 _minGas,
                            uint256 _value,
                            bytes memory _calldata
                        ) internal returns (bool) {
                            bool _success;
                            bool _hasMinGas = hasMinGas(_minGas, 0);
                            assembly {
                                // Assertion: gasleft() >= (_minGas * 64) / 63 + 40_000
                                if iszero(_hasMinGas) {
                                    // Store the "Error(string)" selector in scratch space.
                                    mstore(0, 0x08c379a0)
                                    // Store the pointer to the string length in scratch space.
                                    mstore(32, 32)
                                    // Store the string.
                                    //
                                    // SAFETY:
                                    // - We pad the beginning of the string with two zero bytes as well as the
                                    // length (24) to ensure that we override the free memory pointer at offset
                                    // 0x40. This is necessary because the free memory pointer is likely to
                                    // be greater than 1 byte when this function is called, but it is incredibly
                                    // unlikely that it will be greater than 3 bytes. As for the data within
                                    // 0x60, it is ensured that it is 0 due to 0x60 being the zero offset.
                                    // - It's fine to clobber the free memory pointer, we're reverting.
                                    mstore(88, 0x0000185361666543616c6c3a204e6f7420656e6f75676820676173)
                                    // Revert with 'Error("SafeCall: Not enough gas")'
                                    revert(28, 100)
                                }
                                // The call will be supplied at least ((_minGas * 64) / 63) gas due to the
                                // above assertion. This ensures that, in all circumstances (except for when the
                                // `_minGas` does not account for the `memory_expansion_cost` and `code_execution_cost`
                                // factors of the dynamic cost of the `CALL` opcode), the call will receive at least
                                // the minimum amount of gas specified.
                                _success := call(
                                    gas(), // gas
                                    _target, // recipient
                                    _value, // ether value
                                    add(_calldata, 32), // inloc
                                    mload(_calldata), // inlen
                                    0x00, // outloc
                                    0x00 // outlen
                                )
                            }
                            return _success;
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    pragma solidity ^0.8.0;
                    /**
                     * @title Types
                     * @notice Contains various types used throughout the Optimism contract system.
                     */
                    library Types {
                        /**
                         * @notice OutputProposal represents a commitment to the L2 state. The timestamp is the L1
                         *         timestamp that the output root is posted. This timestamp is used to verify that the
                         *         finalization period has passed since the output root was submitted.
                         *
                         * @custom:field outputRoot    Hash of the L2 output.
                         * @custom:field timestamp     Timestamp of the L1 block that the output root was submitted in.
                         * @custom:field l2BlockNumber L2 block number that the output corresponds to.
                         */
                        struct OutputProposal {
                            bytes32 outputRoot;
                            uint128 timestamp;
                            uint128 l2BlockNumber;
                        }
                        /**
                         * @notice Struct representing the elements that are hashed together to generate an output root
                         *         which itself represents a snapshot of the L2 state.
                         *
                         * @custom:field version                  Version of the output root.
                         * @custom:field stateRoot                Root of the state trie at the block of this output.
                         * @custom:field messagePasserStorageRoot Root of the message passer storage trie.
                         * @custom:field latestBlockhash          Hash of the block this output was generated from.
                         */
                        struct OutputRootProof {
                            bytes32 version;
                            bytes32 stateRoot;
                            bytes32 messagePasserStorageRoot;
                            bytes32 latestBlockhash;
                        }
                        /**
                         * @notice Struct representing a deposit transaction (L1 => L2 transaction) created by an end
                         *         user (as opposed to a system deposit transaction generated by the system).
                         *
                         * @custom:field from        Address of the sender of the transaction.
                         * @custom:field to          Address of the recipient of the transaction.
                         * @custom:field isCreation  True if the transaction is a contract creation.
                         * @custom:field value       Value to send to the recipient.
                         * @custom:field mint        Amount of ETH to mint.
                         * @custom:field gasLimit    Gas limit of the transaction.
                         * @custom:field data        Data of the transaction.
                         * @custom:field l1BlockHash Hash of the block the transaction was submitted in.
                         * @custom:field logIndex    Index of the log in the block the transaction was submitted in.
                         */
                        struct UserDepositTransaction {
                            address from;
                            address to;
                            bool isCreation;
                            uint256 value;
                            uint256 mint;
                            uint64 gasLimit;
                            bytes data;
                            bytes32 l1BlockHash;
                            uint256 logIndex;
                        }
                        /**
                         * @notice Struct representing a withdrawal transaction.
                         *
                         * @custom:field nonce    Nonce of the withdrawal transaction
                         * @custom:field sender   Address of the sender of the transaction.
                         * @custom:field target   Address of the recipient of the transaction.
                         * @custom:field value    Value to send to the recipient.
                         * @custom:field gasLimit Gas limit of the transaction.
                         * @custom:field data     Data of the transaction.
                         */
                        struct WithdrawalTransaction {
                            uint256 nonce;
                            address sender;
                            address target;
                            uint256 value;
                            uint256 gasLimit;
                            bytes data;
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    pragma solidity ^0.8.8;
                    /**
                     * @custom:attribution https://github.com/hamdiallam/Solidity-RLP
                     * @title RLPReader
                     * @notice RLPReader is a library for parsing RLP-encoded byte arrays into Solidity types. Adapted
                     *         from Solidity-RLP (https://github.com/hamdiallam/Solidity-RLP) by Hamdi Allam with
                     *         various tweaks to improve readability.
                     */
                    library RLPReader {
                        /**
                         * Custom pointer type to avoid confusion between pointers and uint256s.
                         */
                        type MemoryPointer is uint256;
                        /**
                         * @notice RLP item types.
                         *
                         * @custom:value DATA_ITEM Represents an RLP data item (NOT a list).
                         * @custom:value LIST_ITEM Represents an RLP list item.
                         */
                        enum RLPItemType {
                            DATA_ITEM,
                            LIST_ITEM
                        }
                        /**
                         * @notice Struct representing an RLP item.
                         *
                         * @custom:field length Length of the RLP item.
                         * @custom:field ptr    Pointer to the RLP item in memory.
                         */
                        struct RLPItem {
                            uint256 length;
                            MemoryPointer ptr;
                        }
                        /**
                         * @notice Max list length that this library will accept.
                         */
                        uint256 internal constant MAX_LIST_LENGTH = 32;
                        /**
                         * @notice Converts bytes to a reference to memory position and length.
                         *
                         * @param _in Input bytes to convert.
                         *
                         * @return Output memory reference.
                         */
                        function toRLPItem(bytes memory _in) internal pure returns (RLPItem memory) {
                            // Empty arrays are not RLP items.
                            require(
                                _in.length > 0,
                                "RLPReader: length of an RLP item must be greater than zero to be decodable"
                            );
                            MemoryPointer ptr;
                            assembly {
                                ptr := add(_in, 32)
                            }
                            return RLPItem({ length: _in.length, ptr: ptr });
                        }
                        /**
                         * @notice Reads an RLP list value into a list of RLP items.
                         *
                         * @param _in RLP list value.
                         *
                         * @return Decoded RLP list items.
                         */
                        function readList(RLPItem memory _in) internal pure returns (RLPItem[] memory) {
                            (uint256 listOffset, uint256 listLength, RLPItemType itemType) = _decodeLength(_in);
                            require(
                                itemType == RLPItemType.LIST_ITEM,
                                "RLPReader: decoded item type for list is not a list item"
                            );
                            require(
                                listOffset + listLength == _in.length,
                                "RLPReader: list item has an invalid data remainder"
                            );
                            // Solidity in-memory arrays can't be increased in size, but *can* be decreased in size by
                            // writing to the length. Since we can't know the number of RLP items without looping over
                            // the entire input, we'd have to loop twice to accurately size this array. It's easier to
                            // simply set a reasonable maximum list length and decrease the size before we finish.
                            RLPItem[] memory out = new RLPItem[](MAX_LIST_LENGTH);
                            uint256 itemCount = 0;
                            uint256 offset = listOffset;
                            while (offset < _in.length) {
                                (uint256 itemOffset, uint256 itemLength, ) = _decodeLength(
                                    RLPItem({
                                        length: _in.length - offset,
                                        ptr: MemoryPointer.wrap(MemoryPointer.unwrap(_in.ptr) + offset)
                                    })
                                );
                                // We don't need to check itemCount < out.length explicitly because Solidity already
                                // handles this check on our behalf, we'd just be wasting gas.
                                out[itemCount] = RLPItem({
                                    length: itemLength + itemOffset,
                                    ptr: MemoryPointer.wrap(MemoryPointer.unwrap(_in.ptr) + offset)
                                });
                                itemCount += 1;
                                offset += itemOffset + itemLength;
                            }
                            // Decrease the array size to match the actual item count.
                            assembly {
                                mstore(out, itemCount)
                            }
                            return out;
                        }
                        /**
                         * @notice Reads an RLP list value into a list of RLP items.
                         *
                         * @param _in RLP list value.
                         *
                         * @return Decoded RLP list items.
                         */
                        function readList(bytes memory _in) internal pure returns (RLPItem[] memory) {
                            return readList(toRLPItem(_in));
                        }
                        /**
                         * @notice Reads an RLP bytes value into bytes.
                         *
                         * @param _in RLP bytes value.
                         *
                         * @return Decoded bytes.
                         */
                        function readBytes(RLPItem memory _in) internal pure returns (bytes memory) {
                            (uint256 itemOffset, uint256 itemLength, RLPItemType itemType) = _decodeLength(_in);
                            require(
                                itemType == RLPItemType.DATA_ITEM,
                                "RLPReader: decoded item type for bytes is not a data item"
                            );
                            require(
                                _in.length == itemOffset + itemLength,
                                "RLPReader: bytes value contains an invalid remainder"
                            );
                            return _copy(_in.ptr, itemOffset, itemLength);
                        }
                        /**
                         * @notice Reads an RLP bytes value into bytes.
                         *
                         * @param _in RLP bytes value.
                         *
                         * @return Decoded bytes.
                         */
                        function readBytes(bytes memory _in) internal pure returns (bytes memory) {
                            return readBytes(toRLPItem(_in));
                        }
                        /**
                         * @notice Reads the raw bytes of an RLP item.
                         *
                         * @param _in RLP item to read.
                         *
                         * @return Raw RLP bytes.
                         */
                        function readRawBytes(RLPItem memory _in) internal pure returns (bytes memory) {
                            return _copy(_in.ptr, 0, _in.length);
                        }
                        /**
                         * @notice Decodes the length of an RLP item.
                         *
                         * @param _in RLP item to decode.
                         *
                         * @return Offset of the encoded data.
                         * @return Length of the encoded data.
                         * @return RLP item type (LIST_ITEM or DATA_ITEM).
                         */
                        function _decodeLength(RLPItem memory _in)
                            private
                            pure
                            returns (
                                uint256,
                                uint256,
                                RLPItemType
                            )
                        {
                            // Short-circuit if there's nothing to decode, note that we perform this check when
                            // the user creates an RLP item via toRLPItem, but it's always possible for them to bypass
                            // that function and create an RLP item directly. So we need to check this anyway.
                            require(
                                _in.length > 0,
                                "RLPReader: length of an RLP item must be greater than zero to be decodable"
                            );
                            MemoryPointer ptr = _in.ptr;
                            uint256 prefix;
                            assembly {
                                prefix := byte(0, mload(ptr))
                            }
                            if (prefix <= 0x7f) {
                                // Single byte.
                                return (0, 1, RLPItemType.DATA_ITEM);
                            } else if (prefix <= 0xb7) {
                                // Short string.
                                // slither-disable-next-line variable-scope
                                uint256 strLen = prefix - 0x80;
                                require(
                                    _in.length > strLen,
                                    "RLPReader: length of content must be greater than string length (short string)"
                                );
                                bytes1 firstByteOfContent;
                                assembly {
                                    firstByteOfContent := and(mload(add(ptr, 1)), shl(248, 0xff))
                                }
                                require(
                                    strLen != 1 || firstByteOfContent >= 0x80,
                                    "RLPReader: invalid prefix, single byte < 0x80 are not prefixed (short string)"
                                );
                                return (1, strLen, RLPItemType.DATA_ITEM);
                            } else if (prefix <= 0xbf) {
                                // Long string.
                                uint256 lenOfStrLen = prefix - 0xb7;
                                require(
                                    _in.length > lenOfStrLen,
                                    "RLPReader: length of content must be > than length of string length (long string)"
                                );
                                bytes1 firstByteOfContent;
                                assembly {
                                    firstByteOfContent := and(mload(add(ptr, 1)), shl(248, 0xff))
                                }
                                require(
                                    firstByteOfContent != 0x00,
                                    "RLPReader: length of content must not have any leading zeros (long string)"
                                );
                                uint256 strLen;
                                assembly {
                                    strLen := shr(sub(256, mul(8, lenOfStrLen)), mload(add(ptr, 1)))
                                }
                                require(
                                    strLen > 55,
                                    "RLPReader: length of content must be greater than 55 bytes (long string)"
                                );
                                require(
                                    _in.length > lenOfStrLen + strLen,
                                    "RLPReader: length of content must be greater than total length (long string)"
                                );
                                return (1 + lenOfStrLen, strLen, RLPItemType.DATA_ITEM);
                            } else if (prefix <= 0xf7) {
                                // Short list.
                                // slither-disable-next-line variable-scope
                                uint256 listLen = prefix - 0xc0;
                                require(
                                    _in.length > listLen,
                                    "RLPReader: length of content must be greater than list length (short list)"
                                );
                                return (1, listLen, RLPItemType.LIST_ITEM);
                            } else {
                                // Long list.
                                uint256 lenOfListLen = prefix - 0xf7;
                                require(
                                    _in.length > lenOfListLen,
                                    "RLPReader: length of content must be > than length of list length (long list)"
                                );
                                bytes1 firstByteOfContent;
                                assembly {
                                    firstByteOfContent := and(mload(add(ptr, 1)), shl(248, 0xff))
                                }
                                require(
                                    firstByteOfContent != 0x00,
                                    "RLPReader: length of content must not have any leading zeros (long list)"
                                );
                                uint256 listLen;
                                assembly {
                                    listLen := shr(sub(256, mul(8, lenOfListLen)), mload(add(ptr, 1)))
                                }
                                require(
                                    listLen > 55,
                                    "RLPReader: length of content must be greater than 55 bytes (long list)"
                                );
                                require(
                                    _in.length > lenOfListLen + listLen,
                                    "RLPReader: length of content must be greater than total length (long list)"
                                );
                                return (1 + lenOfListLen, listLen, RLPItemType.LIST_ITEM);
                            }
                        }
                        /**
                         * @notice Copies the bytes from a memory location.
                         *
                         * @param _src    Pointer to the location to read from.
                         * @param _offset Offset to start reading from.
                         * @param _length Number of bytes to read.
                         *
                         * @return Copied bytes.
                         */
                        function _copy(
                            MemoryPointer _src,
                            uint256 _offset,
                            uint256 _length
                        ) private pure returns (bytes memory) {
                            bytes memory out = new bytes(_length);
                            if (_length == 0) {
                                return out;
                            }
                            // Mostly based on Solidity's copy_memory_to_memory:
                            // solhint-disable max-line-length
                            // https://github.com/ethereum/solidity/blob/34dd30d71b4da730488be72ff6af7083cf2a91f6/libsolidity/codegen/YulUtilFunctions.cpp#L102-L114
                            uint256 src = MemoryPointer.unwrap(_src) + _offset;
                            assembly {
                                let dest := add(out, 32)
                                let i := 0
                                for {
                                } lt(i, _length) {
                                    i := add(i, 32)
                                } {
                                    mstore(add(dest, i), mload(add(src, i)))
                                }
                                if gt(i, _length) {
                                    mstore(add(dest, _length), 0)
                                }
                            }
                            return out;
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    pragma solidity ^0.8.0;
                    /**
                     * @custom:attribution https://github.com/bakaoh/solidity-rlp-encode
                     * @title RLPWriter
                     * @author RLPWriter is a library for encoding Solidity types to RLP bytes. Adapted from Bakaoh's
                     *         RLPEncode library (https://github.com/bakaoh/solidity-rlp-encode) with minor
                     *         modifications to improve legibility.
                     */
                    library RLPWriter {
                        /**
                         * @notice RLP encodes a byte string.
                         *
                         * @param _in The byte string to encode.
                         *
                         * @return The RLP encoded string in bytes.
                         */
                        function writeBytes(bytes memory _in) internal pure returns (bytes memory) {
                            bytes memory encoded;
                            if (_in.length == 1 && uint8(_in[0]) < 128) {
                                encoded = _in;
                            } else {
                                encoded = abi.encodePacked(_writeLength(_in.length, 128), _in);
                            }
                            return encoded;
                        }
                        /**
                         * @notice RLP encodes a list of RLP encoded byte byte strings.
                         *
                         * @param _in The list of RLP encoded byte strings.
                         *
                         * @return The RLP encoded list of items in bytes.
                         */
                        function writeList(bytes[] memory _in) internal pure returns (bytes memory) {
                            bytes memory list = _flatten(_in);
                            return abi.encodePacked(_writeLength(list.length, 192), list);
                        }
                        /**
                         * @notice RLP encodes a string.
                         *
                         * @param _in The string to encode.
                         *
                         * @return The RLP encoded string in bytes.
                         */
                        function writeString(string memory _in) internal pure returns (bytes memory) {
                            return writeBytes(bytes(_in));
                        }
                        /**
                         * @notice RLP encodes an address.
                         *
                         * @param _in The address to encode.
                         *
                         * @return The RLP encoded address in bytes.
                         */
                        function writeAddress(address _in) internal pure returns (bytes memory) {
                            return writeBytes(abi.encodePacked(_in));
                        }
                        /**
                         * @notice RLP encodes a uint.
                         *
                         * @param _in The uint256 to encode.
                         *
                         * @return The RLP encoded uint256 in bytes.
                         */
                        function writeUint(uint256 _in) internal pure returns (bytes memory) {
                            return writeBytes(_toBinary(_in));
                        }
                        /**
                         * @notice RLP encodes a bool.
                         *
                         * @param _in The bool to encode.
                         *
                         * @return The RLP encoded bool in bytes.
                         */
                        function writeBool(bool _in) internal pure returns (bytes memory) {
                            bytes memory encoded = new bytes(1);
                            encoded[0] = (_in ? bytes1(0x01) : bytes1(0x80));
                            return encoded;
                        }
                        /**
                         * @notice Encode the first byte and then the `len` in binary form if `length` is more than 55.
                         *
                         * @param _len    The length of the string or the payload.
                         * @param _offset 128 if item is string, 192 if item is list.
                         *
                         * @return RLP encoded bytes.
                         */
                        function _writeLength(uint256 _len, uint256 _offset) private pure returns (bytes memory) {
                            bytes memory encoded;
                            if (_len < 56) {
                                encoded = new bytes(1);
                                encoded[0] = bytes1(uint8(_len) + uint8(_offset));
                            } else {
                                uint256 lenLen;
                                uint256 i = 1;
                                while (_len / i != 0) {
                                    lenLen++;
                                    i *= 256;
                                }
                                encoded = new bytes(lenLen + 1);
                                encoded[0] = bytes1(uint8(lenLen) + uint8(_offset) + 55);
                                for (i = 1; i <= lenLen; i++) {
                                    encoded[i] = bytes1(uint8((_len / (256**(lenLen - i))) % 256));
                                }
                            }
                            return encoded;
                        }
                        /**
                         * @notice Encode integer in big endian binary form with no leading zeroes.
                         *
                         * @param _x The integer to encode.
                         *
                         * @return RLP encoded bytes.
                         */
                        function _toBinary(uint256 _x) private pure returns (bytes memory) {
                            bytes memory b = abi.encodePacked(_x);
                            uint256 i = 0;
                            for (; i < 32; i++) {
                                if (b[i] != 0) {
                                    break;
                                }
                            }
                            bytes memory res = new bytes(32 - i);
                            for (uint256 j = 0; j < res.length; j++) {
                                res[j] = b[i++];
                            }
                            return res;
                        }
                        /**
                         * @custom:attribution https://github.com/Arachnid/solidity-stringutils
                         * @notice Copies a piece of memory to another location.
                         *
                         * @param _dest Destination location.
                         * @param _src  Source location.
                         * @param _len  Length of memory to copy.
                         */
                        function _memcpy(
                            uint256 _dest,
                            uint256 _src,
                            uint256 _len
                        ) private pure {
                            uint256 dest = _dest;
                            uint256 src = _src;
                            uint256 len = _len;
                            for (; len >= 32; len -= 32) {
                                assembly {
                                    mstore(dest, mload(src))
                                }
                                dest += 32;
                                src += 32;
                            }
                            uint256 mask;
                            unchecked {
                                mask = 256**(32 - len) - 1;
                            }
                            assembly {
                                let srcpart := and(mload(src), not(mask))
                                let destpart := and(mload(dest), mask)
                                mstore(dest, or(destpart, srcpart))
                            }
                        }
                        /**
                         * @custom:attribution https://github.com/sammayo/solidity-rlp-encoder
                         * @notice Flattens a list of byte strings into one byte string.
                         *
                         * @param _list List of byte strings to flatten.
                         *
                         * @return The flattened byte string.
                         */
                        function _flatten(bytes[] memory _list) private pure returns (bytes memory) {
                            if (_list.length == 0) {
                                return new bytes(0);
                            }
                            uint256 len;
                            uint256 i = 0;
                            for (; i < _list.length; i++) {
                                len += _list[i].length;
                            }
                            bytes memory flattened = new bytes(len);
                            uint256 flattenedPtr;
                            assembly {
                                flattenedPtr := add(flattened, 0x20)
                            }
                            for (i = 0; i < _list.length; i++) {
                                bytes memory item = _list[i];
                                uint256 listPtr;
                                assembly {
                                    listPtr := add(item, 0x20)
                                }
                                _memcpy(flattenedPtr, listPtr, item.length);
                                flattenedPtr += _list[i].length;
                            }
                            return flattened;
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    pragma solidity ^0.8.0;
                    import { Bytes } from "../Bytes.sol";
                    import { RLPReader } from "../rlp/RLPReader.sol";
                    /**
                     * @title MerkleTrie
                     * @notice MerkleTrie is a small library for verifying standard Ethereum Merkle-Patricia trie
                     *         inclusion proofs. By default, this library assumes a hexary trie. One can change the
                     *         trie radix constant to support other trie radixes.
                     */
                    library MerkleTrie {
                        /**
                         * @notice Struct representing a node in the trie.
                         *
                         * @custom:field encoded The RLP-encoded node.
                         * @custom:field decoded The RLP-decoded node.
                         */
                        struct TrieNode {
                            bytes encoded;
                            RLPReader.RLPItem[] decoded;
                        }
                        /**
                         * @notice Determines the number of elements per branch node.
                         */
                        uint256 internal constant TREE_RADIX = 16;
                        /**
                         * @notice Branch nodes have TREE_RADIX elements and one value element.
                         */
                        uint256 internal constant BRANCH_NODE_LENGTH = TREE_RADIX + 1;
                        /**
                         * @notice Leaf nodes and extension nodes have two elements, a `path` and a `value`.
                         */
                        uint256 internal constant LEAF_OR_EXTENSION_NODE_LENGTH = 2;
                        /**
                         * @notice Prefix for even-nibbled extension node paths.
                         */
                        uint8 internal constant PREFIX_EXTENSION_EVEN = 0;
                        /**
                         * @notice Prefix for odd-nibbled extension node paths.
                         */
                        uint8 internal constant PREFIX_EXTENSION_ODD = 1;
                        /**
                         * @notice Prefix for even-nibbled leaf node paths.
                         */
                        uint8 internal constant PREFIX_LEAF_EVEN = 2;
                        /**
                         * @notice Prefix for odd-nibbled leaf node paths.
                         */
                        uint8 internal constant PREFIX_LEAF_ODD = 3;
                        /**
                         * @notice Verifies a proof that a given key/value pair is present in the trie.
                         *
                         * @param _key   Key of the node to search for, as a hex string.
                         * @param _value Value of the node to search for, as a hex string.
                         * @param _proof Merkle trie inclusion proof for the desired node. Unlike traditional Merkle
                         *               trees, this proof is executed top-down and consists of a list of RLP-encoded
                         *               nodes that make a path down to the target node.
                         * @param _root  Known root of the Merkle trie. Used to verify that the included proof is
                         *               correctly constructed.
                         *
                         * @return Whether or not the proof is valid.
                         */
                        function verifyInclusionProof(
                            bytes memory _key,
                            bytes memory _value,
                            bytes[] memory _proof,
                            bytes32 _root
                        ) internal pure returns (bool) {
                            return Bytes.equal(_value, get(_key, _proof, _root));
                        }
                        /**
                         * @notice Retrieves the value associated with a given key.
                         *
                         * @param _key   Key to search for, as hex bytes.
                         * @param _proof Merkle trie inclusion proof for the key.
                         * @param _root  Known root of the Merkle trie.
                         *
                         * @return Value of the key if it exists.
                         */
                        function get(
                            bytes memory _key,
                            bytes[] memory _proof,
                            bytes32 _root
                        ) internal pure returns (bytes memory) {
                            require(_key.length > 0, "MerkleTrie: empty key");
                            TrieNode[] memory proof = _parseProof(_proof);
                            bytes memory key = Bytes.toNibbles(_key);
                            bytes memory currentNodeID = abi.encodePacked(_root);
                            uint256 currentKeyIndex = 0;
                            // Proof is top-down, so we start at the first element (root).
                            for (uint256 i = 0; i < proof.length; i++) {
                                TrieNode memory currentNode = proof[i];
                                // Key index should never exceed total key length or we'll be out of bounds.
                                require(
                                    currentKeyIndex <= key.length,
                                    "MerkleTrie: key index exceeds total key length"
                                );
                                if (currentKeyIndex == 0) {
                                    // First proof element is always the root node.
                                    require(
                                        Bytes.equal(abi.encodePacked(keccak256(currentNode.encoded)), currentNodeID),
                                        "MerkleTrie: invalid root hash"
                                    );
                                } else if (currentNode.encoded.length >= 32) {
                                    // Nodes 32 bytes or larger are hashed inside branch nodes.
                                    require(
                                        Bytes.equal(abi.encodePacked(keccak256(currentNode.encoded)), currentNodeID),
                                        "MerkleTrie: invalid large internal hash"
                                    );
                                } else {
                                    // Nodes smaller than 32 bytes aren't hashed.
                                    require(
                                        Bytes.equal(currentNode.encoded, currentNodeID),
                                        "MerkleTrie: invalid internal node hash"
                                    );
                                }
                                if (currentNode.decoded.length == BRANCH_NODE_LENGTH) {
                                    if (currentKeyIndex == key.length) {
                                        // Value is the last element of the decoded list (for branch nodes). There's
                                        // some ambiguity in the Merkle trie specification because bytes(0) is a
                                        // valid value to place into the trie, but for branch nodes bytes(0) can exist
                                        // even when the value wasn't explicitly placed there. Geth treats a value of
                                        // bytes(0) as "key does not exist" and so we do the same.
                                        bytes memory value = RLPReader.readBytes(currentNode.decoded[TREE_RADIX]);
                                        require(
                                            value.length > 0,
                                            "MerkleTrie: value length must be greater than zero (branch)"
                                        );
                                        // Extra proof elements are not allowed.
                                        require(
                                            i == proof.length - 1,
                                            "MerkleTrie: value node must be last node in proof (branch)"
                                        );
                                        return value;
                                    } else {
                                        // We're not at the end of the key yet.
                                        // Figure out what the next node ID should be and continue.
                                        uint8 branchKey = uint8(key[currentKeyIndex]);
                                        RLPReader.RLPItem memory nextNode = currentNode.decoded[branchKey];
                                        currentNodeID = _getNodeID(nextNode);
                                        currentKeyIndex += 1;
                                    }
                                } else if (currentNode.decoded.length == LEAF_OR_EXTENSION_NODE_LENGTH) {
                                    bytes memory path = _getNodePath(currentNode);
                                    uint8 prefix = uint8(path[0]);
                                    uint8 offset = 2 - (prefix % 2);
                                    bytes memory pathRemainder = Bytes.slice(path, offset);
                                    bytes memory keyRemainder = Bytes.slice(key, currentKeyIndex);
                                    uint256 sharedNibbleLength = _getSharedNibbleLength(pathRemainder, keyRemainder);
                                    // Whether this is a leaf node or an extension node, the path remainder MUST be a
                                    // prefix of the key remainder (or be equal to the key remainder) or the proof is
                                    // considered invalid.
                                    require(
                                        pathRemainder.length == sharedNibbleLength,
                                        "MerkleTrie: path remainder must share all nibbles with key"
                                    );
                                    if (prefix == PREFIX_LEAF_EVEN || prefix == PREFIX_LEAF_ODD) {
                                        // Prefix of 2 or 3 means this is a leaf node. For the leaf node to be valid,
                                        // the key remainder must be exactly equal to the path remainder. We already
                                        // did the necessary byte comparison, so it's more efficient here to check that
                                        // the key remainder length equals the shared nibble length, which implies
                                        // equality with the path remainder (since we already did the same check with
                                        // the path remainder and the shared nibble length).
                                        require(
                                            keyRemainder.length == sharedNibbleLength,
                                            "MerkleTrie: key remainder must be identical to path remainder"
                                        );
                                        // Our Merkle Trie is designed specifically for the purposes of the Ethereum
                                        // state trie. Empty values are not allowed in the state trie, so we can safely
                                        // say that if the value is empty, the key should not exist and the proof is
                                        // invalid.
                                        bytes memory value = RLPReader.readBytes(currentNode.decoded[1]);
                                        require(
                                            value.length > 0,
                                            "MerkleTrie: value length must be greater than zero (leaf)"
                                        );
                                        // Extra proof elements are not allowed.
                                        require(
                                            i == proof.length - 1,
                                            "MerkleTrie: value node must be last node in proof (leaf)"
                                        );
                                        return value;
                                    } else if (prefix == PREFIX_EXTENSION_EVEN || prefix == PREFIX_EXTENSION_ODD) {
                                        // Prefix of 0 or 1 means this is an extension node. We move onto the next node
                                        // in the proof and increment the key index by the length of the path remainder
                                        // which is equal to the shared nibble length.
                                        currentNodeID = _getNodeID(currentNode.decoded[1]);
                                        currentKeyIndex += sharedNibbleLength;
                                    } else {
                                        revert("MerkleTrie: received a node with an unknown prefix");
                                    }
                                } else {
                                    revert("MerkleTrie: received an unparseable node");
                                }
                            }
                            revert("MerkleTrie: ran out of proof elements");
                        }
                        /**
                         * @notice Parses an array of proof elements into a new array that contains both the original
                         *         encoded element and the RLP-decoded element.
                         *
                         * @param _proof Array of proof elements to parse.
                         *
                         * @return Proof parsed into easily accessible structs.
                         */
                        function _parseProof(bytes[] memory _proof) private pure returns (TrieNode[] memory) {
                            uint256 length = _proof.length;
                            TrieNode[] memory proof = new TrieNode[](length);
                            for (uint256 i = 0; i < length; ) {
                                proof[i] = TrieNode({ encoded: _proof[i], decoded: RLPReader.readList(_proof[i]) });
                                unchecked {
                                    ++i;
                                }
                            }
                            return proof;
                        }
                        /**
                         * @notice Picks out the ID for a node. Node ID is referred to as the "hash" within the
                         *         specification, but nodes < 32 bytes are not actually hashed.
                         *
                         * @param _node Node to pull an ID for.
                         *
                         * @return ID for the node, depending on the size of its contents.
                         */
                        function _getNodeID(RLPReader.RLPItem memory _node) private pure returns (bytes memory) {
                            return _node.length < 32 ? RLPReader.readRawBytes(_node) : RLPReader.readBytes(_node);
                        }
                        /**
                         * @notice Gets the path for a leaf or extension node.
                         *
                         * @param _node Node to get a path for.
                         *
                         * @return Node path, converted to an array of nibbles.
                         */
                        function _getNodePath(TrieNode memory _node) private pure returns (bytes memory) {
                            return Bytes.toNibbles(RLPReader.readBytes(_node.decoded[0]));
                        }
                        /**
                         * @notice Utility; determines the number of nibbles shared between two nibble arrays.
                         *
                         * @param _a First nibble array.
                         * @param _b Second nibble array.
                         *
                         * @return Number of shared nibbles.
                         */
                        function _getSharedNibbleLength(bytes memory _a, bytes memory _b)
                            private
                            pure
                            returns (uint256)
                        {
                            uint256 shared;
                            uint256 max = (_a.length < _b.length) ? _a.length : _b.length;
                            for (; shared < max && _a[shared] == _b[shared]; ) {
                                unchecked {
                                    ++shared;
                                }
                            }
                            return shared;
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    pragma solidity ^0.8.0;
                    /* Library Imports */
                    import { MerkleTrie } from "./MerkleTrie.sol";
                    /**
                     * @title SecureMerkleTrie
                     * @notice SecureMerkleTrie is a thin wrapper around the MerkleTrie library that hashes the input
                     *         keys. Ethereum's state trie hashes input keys before storing them.
                     */
                    library SecureMerkleTrie {
                        /**
                         * @notice Verifies a proof that a given key/value pair is present in the Merkle trie.
                         *
                         * @param _key   Key of the node to search for, as a hex string.
                         * @param _value Value of the node to search for, as a hex string.
                         * @param _proof Merkle trie inclusion proof for the desired node. Unlike traditional Merkle
                         *               trees, this proof is executed top-down and consists of a list of RLP-encoded
                         *               nodes that make a path down to the target node.
                         * @param _root  Known root of the Merkle trie. Used to verify that the included proof is
                         *               correctly constructed.
                         *
                         * @return Whether or not the proof is valid.
                         */
                        function verifyInclusionProof(
                            bytes memory _key,
                            bytes memory _value,
                            bytes[] memory _proof,
                            bytes32 _root
                        ) internal pure returns (bool) {
                            bytes memory key = _getSecureKey(_key);
                            return MerkleTrie.verifyInclusionProof(key, _value, _proof, _root);
                        }
                        /**
                         * @notice Retrieves the value associated with a given key.
                         *
                         * @param _key   Key to search for, as hex bytes.
                         * @param _proof Merkle trie inclusion proof for the key.
                         * @param _root  Known root of the Merkle trie.
                         *
                         * @return Value of the key if it exists.
                         */
                        function get(
                            bytes memory _key,
                            bytes[] memory _proof,
                            bytes32 _root
                        ) internal pure returns (bytes memory) {
                            bytes memory key = _getSecureKey(_key);
                            return MerkleTrie.get(key, _proof, _root);
                        }
                        /**
                         * @notice Computes the hashed version of the input key.
                         *
                         * @param _key Key to hash.
                         *
                         * @return Hashed version of the key.
                         */
                        function _getSecureKey(bytes memory _key) private pure returns (bytes memory) {
                            return abi.encodePacked(keccak256(_key));
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    pragma solidity 0.8.15;
                    import { Initializable } from "@openzeppelin/contracts-upgradeable/proxy/utils/Initializable.sol";
                    import { SafeCall } from "../libraries/SafeCall.sol";
                    import { Hashing } from "../libraries/Hashing.sol";
                    import { Encoding } from "../libraries/Encoding.sol";
                    import { Constants } from "../libraries/Constants.sol";
                    /**
                     * @custom:legacy
                     * @title CrossDomainMessengerLegacySpacer0
                     * @notice Contract only exists to add a spacer to the CrossDomainMessenger where the
                     *         libAddressManager variable used to exist. Must be the first contract in the inheritance
                     *         tree of the CrossDomainMessenger.
                     */
                    contract CrossDomainMessengerLegacySpacer0 {
                        /**
                         * @custom:legacy
                         * @custom:spacer libAddressManager
                         * @notice Spacer for backwards compatibility.
                         */
                        address private spacer_0_0_20;
                    }
                    /**
                     * @custom:legacy
                     * @title CrossDomainMessengerLegacySpacer1
                     * @notice Contract only exists to add a spacer to the CrossDomainMessenger where the
                     *         PausableUpgradable and OwnableUpgradeable variables used to exist. Must be
                     *         the third contract in the inheritance tree of the CrossDomainMessenger.
                     */
                    contract CrossDomainMessengerLegacySpacer1 {
                        /**
                         * @custom:legacy
                         * @custom:spacer ContextUpgradable's __gap
                         * @notice Spacer for backwards compatibility. Comes from OpenZeppelin
                         *         ContextUpgradable.
                         *
                         */
                        uint256[50] private spacer_1_0_1600;
                        /**
                         * @custom:legacy
                         * @custom:spacer OwnableUpgradeable's _owner
                         * @notice Spacer for backwards compatibility.
                         *         Come from OpenZeppelin OwnableUpgradeable.
                         */
                        address private spacer_51_0_20;
                        /**
                         * @custom:legacy
                         * @custom:spacer OwnableUpgradeable's __gap
                         * @notice Spacer for backwards compatibility. Comes from OpenZeppelin
                         *         OwnableUpgradeable.
                         */
                        uint256[49] private spacer_52_0_1568;
                        /**
                         * @custom:legacy
                         * @custom:spacer PausableUpgradable's _paused
                         * @notice Spacer for backwards compatibility. Comes from OpenZeppelin
                         *         PausableUpgradable.
                         */
                        bool private spacer_101_0_1;
                        /**
                         * @custom:legacy
                         * @custom:spacer PausableUpgradable's __gap
                         * @notice Spacer for backwards compatibility. Comes from OpenZeppelin
                         *         PausableUpgradable.
                         */
                        uint256[49] private spacer_102_0_1568;
                        /**
                         * @custom:legacy
                         * @custom:spacer ReentrancyGuardUpgradeable's `_status` field.
                         * @notice Spacer for backwards compatibility.
                         */
                        uint256 private spacer_151_0_32;
                        /**
                         * @custom:legacy
                         * @custom:spacer ReentrancyGuardUpgradeable's __gap
                         * @notice Spacer for backwards compatibility.
                         */
                        uint256[49] private spacer_152_0_1568;
                        /**
                         * @custom:legacy
                         * @custom:spacer blockedMessages
                         * @notice Spacer for backwards compatibility.
                         */
                        mapping(bytes32 => bool) private spacer_201_0_32;
                        /**
                         * @custom:legacy
                         * @custom:spacer relayedMessages
                         * @notice Spacer for backwards compatibility.
                         */
                        mapping(bytes32 => bool) private spacer_202_0_32;
                    }
                    /**
                     * @custom:upgradeable
                     * @title CrossDomainMessenger
                     * @notice CrossDomainMessenger is a base contract that provides the core logic for the L1 and L2
                     *         cross-chain messenger contracts. It's designed to be a universal interface that only
                     *         needs to be extended slightly to provide low-level message passing functionality on each
                     *         chain it's deployed on. Currently only designed for message passing between two paired
                     *         chains and does not support one-to-many interactions.
                     *
                     *         Any changes to this contract MUST result in a semver bump for contracts that inherit it.
                     */
                    abstract contract CrossDomainMessenger is
                        CrossDomainMessengerLegacySpacer0,
                        Initializable,
                        CrossDomainMessengerLegacySpacer1
                    {
                        /**
                         * @notice Current message version identifier.
                         */
                        uint16 public constant MESSAGE_VERSION = 1;
                        /**
                         * @notice Constant overhead added to the base gas for a message.
                         */
                        uint64 public constant RELAY_CONSTANT_OVERHEAD = 200_000;
                        /**
                         * @notice Numerator for dynamic overhead added to the base gas for a message.
                         */
                        uint64 public constant MIN_GAS_DYNAMIC_OVERHEAD_NUMERATOR = 64;
                        /**
                         * @notice Denominator for dynamic overhead added to the base gas for a message.
                         */
                        uint64 public constant MIN_GAS_DYNAMIC_OVERHEAD_DENOMINATOR = 63;
                        /**
                         * @notice Extra gas added to base gas for each byte of calldata in a message.
                         */
                        uint64 public constant MIN_GAS_CALLDATA_OVERHEAD = 16;
                        /**
                         * @notice Gas reserved for performing the external call in `relayMessage`.
                         */
                        uint64 public constant RELAY_CALL_OVERHEAD = 40_000;
                        /**
                         * @notice Gas reserved for finalizing the execution of `relayMessage` after the safe call.
                         */
                        uint64 public constant RELAY_RESERVED_GAS = 40_000;
                        /**
                         * @notice Gas reserved for the execution between the `hasMinGas` check and the external
                         *         call in `relayMessage`.
                         */
                        uint64 public constant RELAY_GAS_CHECK_BUFFER = 5_000;
                        /**
                         * @notice Address of the paired CrossDomainMessenger contract on the other chain.
                         */
                        address public immutable OTHER_MESSENGER;
                        /**
                         * @notice Mapping of message hashes to boolean receipt values. Note that a message will only
                         *         be present in this mapping if it has successfully been relayed on this chain, and
                         *         can therefore not be relayed again.
                         */
                        mapping(bytes32 => bool) public successfulMessages;
                        /**
                         * @notice Address of the sender of the currently executing message on the other chain. If the
                         *         value of this variable is the default value (0x00000000...dead) then no message is
                         *         currently being executed. Use the xDomainMessageSender getter which will throw an
                         *         error if this is the case.
                         */
                        address internal xDomainMsgSender;
                        /**
                         * @notice Nonce for the next message to be sent, without the message version applied. Use the
                         *         messageNonce getter which will insert the message version into the nonce to give you
                         *         the actual nonce to be used for the message.
                         */
                        uint240 internal msgNonce;
                        /**
                         * @notice Mapping of message hashes to a boolean if and only if the message has failed to be
                         *         executed at least once. A message will not be present in this mapping if it
                         *         successfully executed on the first attempt.
                         */
                        mapping(bytes32 => bool) public failedMessages;
                        /**
                         * @notice Reserve extra slots in the storage layout for future upgrades.
                         *         A gap size of 41 was chosen here, so that the first slot used in a child contract
                         *         would be a multiple of 50.
                         */
                        uint256[42] private __gap;
                        /**
                         * @notice Emitted whenever a message is sent to the other chain.
                         *
                         * @param target       Address of the recipient of the message.
                         * @param sender       Address of the sender of the message.
                         * @param message      Message to trigger the recipient address with.
                         * @param messageNonce Unique nonce attached to the message.
                         * @param gasLimit     Minimum gas limit that the message can be executed with.
                         */
                        event SentMessage(
                            address indexed target,
                            address sender,
                            bytes message,
                            uint256 messageNonce,
                            uint256 gasLimit
                        );
                        /**
                         * @notice Additional event data to emit, required as of Bedrock. Cannot be merged with the
                         *         SentMessage event without breaking the ABI of this contract, this is good enough.
                         *
                         * @param sender Address of the sender of the message.
                         * @param value  ETH value sent along with the message to the recipient.
                         */
                        event SentMessageExtension1(address indexed sender, uint256 value);
                        /**
                         * @notice Emitted whenever a message is successfully relayed on this chain.
                         *
                         * @param msgHash Hash of the message that was relayed.
                         */
                        event RelayedMessage(bytes32 indexed msgHash);
                        /**
                         * @notice Emitted whenever a message fails to be relayed on this chain.
                         *
                         * @param msgHash Hash of the message that failed to be relayed.
                         */
                        event FailedRelayedMessage(bytes32 indexed msgHash);
                        /**
                         * @param _otherMessenger Address of the messenger on the paired chain.
                         */
                        constructor(address _otherMessenger) {
                            OTHER_MESSENGER = _otherMessenger;
                        }
                        /**
                         * @notice Sends a message to some target address on the other chain. Note that if the call
                         *         always reverts, then the message will be unrelayable, and any ETH sent will be
                         *         permanently locked. The same will occur if the target on the other chain is
                         *         considered unsafe (see the _isUnsafeTarget() function).
                         *
                         * @param _target      Target contract or wallet address.
                         * @param _message     Message to trigger the target address with.
                         * @param _minGasLimit Minimum gas limit that the message can be executed with.
                         */
                        function sendMessage(
                            address _target,
                            bytes calldata _message,
                            uint32 _minGasLimit
                        ) external payable {
                            // Triggers a message to the other messenger. Note that the amount of gas provided to the
                            // message is the amount of gas requested by the user PLUS the base gas value. We want to
                            // guarantee the property that the call to the target contract will always have at least
                            // the minimum gas limit specified by the user.
                            _sendMessage(
                                OTHER_MESSENGER,
                                baseGas(_message, _minGasLimit),
                                msg.value,
                                abi.encodeWithSelector(
                                    this.relayMessage.selector,
                                    messageNonce(),
                                    msg.sender,
                                    _target,
                                    msg.value,
                                    _minGasLimit,
                                    _message
                                )
                            );
                            emit SentMessage(_target, msg.sender, _message, messageNonce(), _minGasLimit);
                            emit SentMessageExtension1(msg.sender, msg.value);
                            unchecked {
                                ++msgNonce;
                            }
                        }
                        /**
                         * @notice Relays a message that was sent by the other CrossDomainMessenger contract. Can only
                         *         be executed via cross-chain call from the other messenger OR if the message was
                         *         already received once and is currently being replayed.
                         *
                         * @param _nonce       Nonce of the message being relayed.
                         * @param _sender      Address of the user who sent the message.
                         * @param _target      Address that the message is targeted at.
                         * @param _value       ETH value to send with the message.
                         * @param _minGasLimit Minimum amount of gas that the message can be executed with.
                         * @param _message     Message to send to the target.
                         */
                        function relayMessage(
                            uint256 _nonce,
                            address _sender,
                            address _target,
                            uint256 _value,
                            uint256 _minGasLimit,
                            bytes calldata _message
                        ) external payable {
                            (, uint16 version) = Encoding.decodeVersionedNonce(_nonce);
                            require(
                                version < 2,
                                "CrossDomainMessenger: only version 0 or 1 messages are supported at this time"
                            );
                            // If the message is version 0, then it's a migrated legacy withdrawal. We therefore need
                            // to check that the legacy version of the message has not already been relayed.
                            if (version == 0) {
                                bytes32 oldHash = Hashing.hashCrossDomainMessageV0(_target, _sender, _message, _nonce);
                                require(
                                    successfulMessages[oldHash] == false,
                                    "CrossDomainMessenger: legacy withdrawal already relayed"
                                );
                            }
                            // We use the v1 message hash as the unique identifier for the message because it commits
                            // to the value and minimum gas limit of the message.
                            bytes32 versionedHash = Hashing.hashCrossDomainMessageV1(
                                _nonce,
                                _sender,
                                _target,
                                _value,
                                _minGasLimit,
                                _message
                            );
                            if (_isOtherMessenger()) {
                                // These properties should always hold when the message is first submitted (as
                                // opposed to being replayed).
                                assert(msg.value == _value);
                                assert(!failedMessages[versionedHash]);
                            } else {
                                require(
                                    msg.value == 0,
                                    "CrossDomainMessenger: value must be zero unless message is from a system address"
                                );
                                require(
                                    failedMessages[versionedHash],
                                    "CrossDomainMessenger: message cannot be replayed"
                                );
                            }
                            require(
                                _isUnsafeTarget(_target) == false,
                                "CrossDomainMessenger: cannot send message to blocked system address"
                            );
                            require(
                                successfulMessages[versionedHash] == false,
                                "CrossDomainMessenger: message has already been relayed"
                            );
                            // If there is not enough gas left to perform the external call and finish the execution,
                            // return early and assign the message to the failedMessages mapping.
                            // We are asserting that we have enough gas to:
                            // 1. Call the target contract (_minGasLimit + RELAY_CALL_OVERHEAD + RELAY_GAS_CHECK_BUFFER)
                            //   1.a. The RELAY_CALL_OVERHEAD is included in `hasMinGas`.
                            // 2. Finish the execution after the external call (RELAY_RESERVED_GAS).
                            //
                            // If `xDomainMsgSender` is not the default L2 sender, this function
                            // is being re-entered. This marks the message as failed to allow it to be replayed.
                            if (
                                !SafeCall.hasMinGas(_minGasLimit, RELAY_RESERVED_GAS + RELAY_GAS_CHECK_BUFFER) ||
                                xDomainMsgSender != Constants.DEFAULT_L2_SENDER
                            ) {
                                failedMessages[versionedHash] = true;
                                emit FailedRelayedMessage(versionedHash);
                                // Revert in this case if the transaction was triggered by the estimation address. This
                                // should only be possible during gas estimation or we have bigger problems. Reverting
                                // here will make the behavior of gas estimation change such that the gas limit
                                // computed will be the amount required to relay the message, even if that amount is
                                // greater than the minimum gas limit specified by the user.
                                if (tx.origin == Constants.ESTIMATION_ADDRESS) {
                                    revert("CrossDomainMessenger: failed to relay message");
                                }
                                return;
                            }
                            xDomainMsgSender = _sender;
                            bool success = SafeCall.call(_target, gasleft() - RELAY_RESERVED_GAS, _value, _message);
                            xDomainMsgSender = Constants.DEFAULT_L2_SENDER;
                            if (success) {
                                successfulMessages[versionedHash] = true;
                                emit RelayedMessage(versionedHash);
                            } else {
                                failedMessages[versionedHash] = true;
                                emit FailedRelayedMessage(versionedHash);
                                // Revert in this case if the transaction was triggered by the estimation address. This
                                // should only be possible during gas estimation or we have bigger problems. Reverting
                                // here will make the behavior of gas estimation change such that the gas limit
                                // computed will be the amount required to relay the message, even if that amount is
                                // greater than the minimum gas limit specified by the user.
                                if (tx.origin == Constants.ESTIMATION_ADDRESS) {
                                    revert("CrossDomainMessenger: failed to relay message");
                                }
                            }
                        }
                        /**
                         * @notice Retrieves the address of the contract or wallet that initiated the currently
                         *         executing message on the other chain. Will throw an error if there is no message
                         *         currently being executed. Allows the recipient of a call to see who triggered it.
                         *
                         * @return Address of the sender of the currently executing message on the other chain.
                         */
                        function xDomainMessageSender() external view returns (address) {
                            require(
                                xDomainMsgSender != Constants.DEFAULT_L2_SENDER,
                                "CrossDomainMessenger: xDomainMessageSender is not set"
                            );
                            return xDomainMsgSender;
                        }
                        /**
                         * @notice Retrieves the next message nonce. Message version will be added to the upper two
                         *         bytes of the message nonce. Message version allows us to treat messages as having
                         *         different structures.
                         *
                         * @return Nonce of the next message to be sent, with added message version.
                         */
                        function messageNonce() public view returns (uint256) {
                            return Encoding.encodeVersionedNonce(msgNonce, MESSAGE_VERSION);
                        }
                        /**
                         * @notice Computes the amount of gas required to guarantee that a given message will be
                         *         received on the other chain without running out of gas. Guaranteeing that a message
                         *         will not run out of gas is important because this ensures that a message can always
                         *         be replayed on the other chain if it fails to execute completely.
                         *
                         * @param _message     Message to compute the amount of required gas for.
                         * @param _minGasLimit Minimum desired gas limit when message goes to target.
                         *
                         * @return Amount of gas required to guarantee message receipt.
                         */
                        function baseGas(bytes calldata _message, uint32 _minGasLimit) public pure returns (uint64) {
                            return
                                // Constant overhead
                                RELAY_CONSTANT_OVERHEAD +
                                // Calldata overhead
                                (uint64(_message.length) * MIN_GAS_CALLDATA_OVERHEAD) +
                                // Dynamic overhead (EIP-150)
                                ((_minGasLimit * MIN_GAS_DYNAMIC_OVERHEAD_NUMERATOR) /
                                    MIN_GAS_DYNAMIC_OVERHEAD_DENOMINATOR) +
                                // Gas reserved for the worst-case cost of 3/5 of the `CALL` opcode's dynamic gas
                                // factors. (Conservative)
                                RELAY_CALL_OVERHEAD +
                                // Relay reserved gas (to ensure execution of `relayMessage` completes after the
                                // subcontext finishes executing) (Conservative)
                                RELAY_RESERVED_GAS +
                                // Gas reserved for the execution between the `hasMinGas` check and the `CALL`
                                // opcode. (Conservative)
                                RELAY_GAS_CHECK_BUFFER;
                        }
                        /**
                         * @notice Intializer.
                         */
                        // solhint-disable-next-line func-name-mixedcase
                        function __CrossDomainMessenger_init() internal onlyInitializing {
                            xDomainMsgSender = Constants.DEFAULT_L2_SENDER;
                        }
                        /**
                         * @notice Sends a low-level message to the other messenger. Needs to be implemented by child
                         *         contracts because the logic for this depends on the network where the messenger is
                         *         being deployed.
                         *
                         * @param _to       Recipient of the message on the other chain.
                         * @param _gasLimit Minimum gas limit the message can be executed with.
                         * @param _value    Amount of ETH to send with the message.
                         * @param _data     Message data.
                         */
                        function _sendMessage(
                            address _to,
                            uint64 _gasLimit,
                            uint256 _value,
                            bytes memory _data
                        ) internal virtual;
                        /**
                         * @notice Checks whether the message is coming from the other messenger. Implemented by child
                         *         contracts because the logic for this depends on the network where the messenger is
                         *         being deployed.
                         *
                         * @return Whether the message is coming from the other messenger.
                         */
                        function _isOtherMessenger() internal view virtual returns (bool);
                        /**
                         * @notice Checks whether a given call target is a system address that could cause the
                         *         messenger to peform an unsafe action. This is NOT a mechanism for blocking user
                         *         addresses. This is ONLY used to prevent the execution of messages to specific
                         *         system addresses that could cause security issues, e.g., having the
                         *         CrossDomainMessenger send messages to itself.
                         *
                         * @param _target Address of the contract to check.
                         *
                         * @return Whether or not the address is an unsafe system address.
                         */
                        function _isUnsafeTarget(address _target) internal view virtual returns (bool);
                    }
                    // SPDX-License-Identifier: MIT
                    pragma solidity ^0.8.0;
                    import { Strings } from "@openzeppelin/contracts/utils/Strings.sol";
                    /**
                     * @title Semver
                     * @notice Semver is a simple contract for managing contract versions.
                     */
                    contract Semver {
                        /**
                         * @notice Contract version number (major).
                         */
                        uint256 private immutable MAJOR_VERSION;
                        /**
                         * @notice Contract version number (minor).
                         */
                        uint256 private immutable MINOR_VERSION;
                        /**
                         * @notice Contract version number (patch).
                         */
                        uint256 private immutable PATCH_VERSION;
                        /**
                         * @param _major Version number (major).
                         * @param _minor Version number (minor).
                         * @param _patch Version number (patch).
                         */
                        constructor(
                            uint256 _major,
                            uint256 _minor,
                            uint256 _patch
                        ) {
                            MAJOR_VERSION = _major;
                            MINOR_VERSION = _minor;
                            PATCH_VERSION = _patch;
                        }
                        /**
                         * @notice Returns the full semver contract version.
                         *
                         * @return Semver contract version as a string.
                         */
                        function version() public view returns (string memory) {
                            return
                                string(
                                    abi.encodePacked(
                                        Strings.toString(MAJOR_VERSION),
                                        ".",
                                        Strings.toString(MINOR_VERSION),
                                        ".",
                                        Strings.toString(PATCH_VERSION)
                                    )
                                );
                        }
                    }
                    // SPDX-License-Identifier: Apache-2.0
                    /*
                     * Copyright 2019-2021, Offchain Labs, Inc.
                     *
                     * Licensed under the Apache License, Version 2.0 (the "License");
                     * you may not use this file except in compliance with the License.
                     * You may obtain a copy of the License at
                     *
                     *    http://www.apache.org/licenses/LICENSE-2.0
                     *
                     * Unless required by applicable law or agreed to in writing, software
                     * distributed under the License is distributed on an "AS IS" BASIS,
                     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
                     * See the License for the specific language governing permissions and
                     * limitations under the License.
                     */
                    pragma solidity ^0.8.0;
                    library AddressAliasHelper {
                        uint160 constant offset = uint160(0x1111000000000000000000000000000000001111);
                        /// @notice Utility function that converts the address in the L1 that submitted a tx to
                        /// the inbox to the msg.sender viewed in the L2
                        /// @param l1Address the address in the L1 that triggered the tx to L2
                        /// @return l2Address L2 address as viewed in msg.sender
                        function applyL1ToL2Alias(address l1Address) internal pure returns (address l2Address) {
                            unchecked {
                                l2Address = address(uint160(l1Address) + offset);
                            }
                        }
                        /// @notice Utility function that converts the msg.sender viewed in the L2 to the
                        /// address in the L1 that submitted a tx to the inbox
                        /// @param l2Address L2 address as viewed in msg.sender
                        /// @return l1Address the address in the L1 that triggered the tx to L2
                        function undoL1ToL2Alias(address l2Address) internal pure returns (address l1Address) {
                            unchecked {
                                l1Address = address(uint160(l2Address) - offset);
                            }
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    // OpenZeppelin Contracts (last updated v4.7.0) (proxy/utils/Initializable.sol)
                    pragma solidity ^0.8.2;
                    import "../../utils/Address.sol";
                    /**
                     * @dev This is a base contract to aid in writing upgradeable contracts, or any kind of contract that will be deployed
                     * behind a proxy. Since proxied contracts do not make use of a constructor, it's common to move constructor logic to an
                     * external initializer function, usually called `initialize`. It then becomes necessary to protect this initializer
                     * function so it can only be called once. The {initializer} modifier provided by this contract will have this effect.
                     *
                     * The initialization functions use a version number. Once a version number is used, it is consumed and cannot be
                     * reused. This mechanism prevents re-execution of each "step" but allows the creation of new initialization steps in
                     * case an upgrade adds a module that needs to be initialized.
                     *
                     * For example:
                     *
                     * [.hljs-theme-light.nopadding]
                     * ```
                     * contract MyToken is ERC20Upgradeable {
                     *     function initialize() initializer public {
                     *         __ERC20_init("MyToken", "MTK");
                     *     }
                     * }
                     * contract MyTokenV2 is MyToken, ERC20PermitUpgradeable {
                     *     function initializeV2() reinitializer(2) public {
                     *         __ERC20Permit_init("MyToken");
                     *     }
                     * }
                     * ```
                     *
                     * TIP: To avoid leaving the proxy in an uninitialized state, the initializer function should be called as early as
                     * possible by providing the encoded function call as the `_data` argument to {ERC1967Proxy-constructor}.
                     *
                     * CAUTION: When used with inheritance, manual care must be taken to not invoke a parent initializer twice, or to ensure
                     * that all initializers are idempotent. This is not verified automatically as constructors are by Solidity.
                     *
                     * [CAUTION]
                     * ====
                     * Avoid leaving a contract uninitialized.
                     *
                     * An uninitialized contract can be taken over by an attacker. This applies to both a proxy and its implementation
                     * contract, which may impact the proxy. To prevent the implementation contract from being used, you should invoke
                     * the {_disableInitializers} function in the constructor to automatically lock it when it is deployed:
                     *
                     * [.hljs-theme-light.nopadding]
                     * ```
                     * /// @custom:oz-upgrades-unsafe-allow constructor
                     * constructor() {
                     *     _disableInitializers();
                     * }
                     * ```
                     * ====
                     */
                    abstract contract Initializable {
                        /**
                         * @dev Indicates that the contract has been initialized.
                         * @custom:oz-retyped-from bool
                         */
                        uint8 private _initialized;
                        /**
                         * @dev Indicates that the contract is in the process of being initialized.
                         */
                        bool private _initializing;
                        /**
                         * @dev Triggered when the contract has been initialized or reinitialized.
                         */
                        event Initialized(uint8 version);
                        /**
                         * @dev A modifier that defines a protected initializer function that can be invoked at most once. In its scope,
                         * `onlyInitializing` functions can be used to initialize parent contracts. Equivalent to `reinitializer(1)`.
                         */
                        modifier initializer() {
                            bool isTopLevelCall = !_initializing;
                            require(
                                (isTopLevelCall && _initialized < 1) || (!Address.isContract(address(this)) && _initialized == 1),
                                "Initializable: contract is already initialized"
                            );
                            _initialized = 1;
                            if (isTopLevelCall) {
                                _initializing = true;
                            }
                            _;
                            if (isTopLevelCall) {
                                _initializing = false;
                                emit Initialized(1);
                            }
                        }
                        /**
                         * @dev A modifier that defines a protected reinitializer function that can be invoked at most once, and only if the
                         * contract hasn't been initialized to a greater version before. In its scope, `onlyInitializing` functions can be
                         * used to initialize parent contracts.
                         *
                         * `initializer` is equivalent to `reinitializer(1)`, so a reinitializer may be used after the original
                         * initialization step. This is essential to configure modules that are added through upgrades and that require
                         * initialization.
                         *
                         * Note that versions can jump in increments greater than 1; this implies that if multiple reinitializers coexist in
                         * a contract, executing them in the right order is up to the developer or operator.
                         */
                        modifier reinitializer(uint8 version) {
                            require(!_initializing && _initialized < version, "Initializable: contract is already initialized");
                            _initialized = version;
                            _initializing = true;
                            _;
                            _initializing = false;
                            emit Initialized(version);
                        }
                        /**
                         * @dev Modifier to protect an initialization function so that it can only be invoked by functions with the
                         * {initializer} and {reinitializer} modifiers, directly or indirectly.
                         */
                        modifier onlyInitializing() {
                            require(_initializing, "Initializable: contract is not initializing");
                            _;
                        }
                        /**
                         * @dev Locks the contract, preventing any future reinitialization. This cannot be part of an initializer call.
                         * Calling this in the constructor of a contract will prevent that contract from being initialized or reinitialized
                         * to any version. It is recommended to use this to lock implementation contracts that are designed to be called
                         * through proxies.
                         */
                        function _disableInitializers() internal virtual {
                            require(!_initializing, "Initializable: contract is initializing");
                            if (_initialized < type(uint8).max) {
                                _initialized = type(uint8).max;
                                emit Initialized(type(uint8).max);
                            }
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    // OpenZeppelin Contracts (last updated v4.7.0) (utils/Address.sol)
                    pragma solidity ^0.8.1;
                    /**
                     * @dev Collection of functions related to the address type
                     */
                    library Address {
                        /**
                         * @dev Returns true if `account` is a contract.
                         *
                         * [IMPORTANT]
                         * ====
                         * It is unsafe to assume that an address for which this function returns
                         * false is an externally-owned account (EOA) and not a contract.
                         *
                         * Among others, `isContract` will return false for the following
                         * types of addresses:
                         *
                         *  - an externally-owned account
                         *  - a contract in construction
                         *  - an address where a contract will be created
                         *  - an address where a contract lived, but was destroyed
                         * ====
                         *
                         * [IMPORTANT]
                         * ====
                         * You shouldn't rely on `isContract` to protect against flash loan attacks!
                         *
                         * Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets
                         * like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract
                         * constructor.
                         * ====
                         */
                        function isContract(address account) internal view returns (bool) {
                            // This method relies on extcodesize/address.code.length, which returns 0
                            // for contracts in construction, since the code is only stored at the end
                            // of the constructor execution.
                            return account.code.length > 0;
                        }
                        /**
                         * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
                         * `recipient`, forwarding all available gas and reverting on errors.
                         *
                         * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
                         * of certain opcodes, possibly making contracts go over the 2300 gas limit
                         * imposed by `transfer`, making them unable to receive funds via
                         * `transfer`. {sendValue} removes this limitation.
                         *
                         * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
                         *
                         * IMPORTANT: because control is transferred to `recipient`, care must be
                         * taken to not create reentrancy vulnerabilities. Consider using
                         * {ReentrancyGuard} or the
                         * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
                         */
                        function sendValue(address payable recipient, uint256 amount) internal {
                            require(address(this).balance >= amount, "Address: insufficient balance");
                            (bool success, ) = recipient.call{value: amount}("");
                            require(success, "Address: unable to send value, recipient may have reverted");
                        }
                        /**
                         * @dev Performs a Solidity function call using a low level `call`. A
                         * plain `call` is an unsafe replacement for a function call: use this
                         * function instead.
                         *
                         * If `target` reverts with a revert reason, it is bubbled up by this
                         * function (like regular Solidity function calls).
                         *
                         * Returns the raw returned data. To convert to the expected return value,
                         * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
                         *
                         * Requirements:
                         *
                         * - `target` must be a contract.
                         * - calling `target` with `data` must not revert.
                         *
                         * _Available since v3.1._
                         */
                        function functionCall(address target, bytes memory data) internal returns (bytes memory) {
                            return functionCall(target, data, "Address: low-level call failed");
                        }
                        /**
                         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
                         * `errorMessage` as a fallback revert reason when `target` reverts.
                         *
                         * _Available since v3.1._
                         */
                        function functionCall(
                            address target,
                            bytes memory data,
                            string memory errorMessage
                        ) internal returns (bytes memory) {
                            return functionCallWithValue(target, data, 0, errorMessage);
                        }
                        /**
                         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
                         * but also transferring `value` wei to `target`.
                         *
                         * Requirements:
                         *
                         * - the calling contract must have an ETH balance of at least `value`.
                         * - the called Solidity function must be `payable`.
                         *
                         * _Available since v3.1._
                         */
                        function functionCallWithValue(
                            address target,
                            bytes memory data,
                            uint256 value
                        ) internal returns (bytes memory) {
                            return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
                        }
                        /**
                         * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
                         * with `errorMessage` as a fallback revert reason when `target` reverts.
                         *
                         * _Available since v3.1._
                         */
                        function functionCallWithValue(
                            address target,
                            bytes memory data,
                            uint256 value,
                            string memory errorMessage
                        ) internal returns (bytes memory) {
                            require(address(this).balance >= value, "Address: insufficient balance for call");
                            require(isContract(target), "Address: call to non-contract");
                            (bool success, bytes memory returndata) = target.call{value: value}(data);
                            return verifyCallResult(success, returndata, errorMessage);
                        }
                        /**
                         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
                         * but performing a static call.
                         *
                         * _Available since v3.3._
                         */
                        function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
                            return functionStaticCall(target, data, "Address: low-level static call failed");
                        }
                        /**
                         * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
                         * but performing a static call.
                         *
                         * _Available since v3.3._
                         */
                        function functionStaticCall(
                            address target,
                            bytes memory data,
                            string memory errorMessage
                        ) internal view returns (bytes memory) {
                            require(isContract(target), "Address: static call to non-contract");
                            (bool success, bytes memory returndata) = target.staticcall(data);
                            return verifyCallResult(success, returndata, errorMessage);
                        }
                        /**
                         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
                         * but performing a delegate call.
                         *
                         * _Available since v3.4._
                         */
                        function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
                            return functionDelegateCall(target, data, "Address: low-level delegate call failed");
                        }
                        /**
                         * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
                         * but performing a delegate call.
                         *
                         * _Available since v3.4._
                         */
                        function functionDelegateCall(
                            address target,
                            bytes memory data,
                            string memory errorMessage
                        ) internal returns (bytes memory) {
                            require(isContract(target), "Address: delegate call to non-contract");
                            (bool success, bytes memory returndata) = target.delegatecall(data);
                            return verifyCallResult(success, returndata, errorMessage);
                        }
                        /**
                         * @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the
                         * revert reason using the provided one.
                         *
                         * _Available since v4.3._
                         */
                        function verifyCallResult(
                            bool success,
                            bytes memory returndata,
                            string memory errorMessage
                        ) internal pure returns (bytes memory) {
                            if (success) {
                                return returndata;
                            } else {
                                // Look for revert reason and bubble it up if present
                                if (returndata.length > 0) {
                                    // The easiest way to bubble the revert reason is using memory via assembly
                                    /// @solidity memory-safe-assembly
                                    assembly {
                                        let returndata_size := mload(returndata)
                                        revert(add(32, returndata), returndata_size)
                                    }
                                } else {
                                    revert(errorMessage);
                                }
                            }
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    // OpenZeppelin Contracts (last updated v4.7.0) (utils/Strings.sol)
                    pragma solidity ^0.8.0;
                    /**
                     * @dev String operations.
                     */
                    library Strings {
                        bytes16 private constant _HEX_SYMBOLS = "0123456789abcdef";
                        uint8 private constant _ADDRESS_LENGTH = 20;
                        /**
                         * @dev Converts a `uint256` to its ASCII `string` decimal representation.
                         */
                        function toString(uint256 value) internal pure returns (string memory) {
                            // Inspired by OraclizeAPI's implementation - MIT licence
                            // https://github.com/oraclize/ethereum-api/blob/b42146b063c7d6ee1358846c198246239e9360e8/oraclizeAPI_0.4.25.sol
                            if (value == 0) {
                                return "0";
                            }
                            uint256 temp = value;
                            uint256 digits;
                            while (temp != 0) {
                                digits++;
                                temp /= 10;
                            }
                            bytes memory buffer = new bytes(digits);
                            while (value != 0) {
                                digits -= 1;
                                buffer[digits] = bytes1(uint8(48 + uint256(value % 10)));
                                value /= 10;
                            }
                            return string(buffer);
                        }
                        /**
                         * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation.
                         */
                        function toHexString(uint256 value) internal pure returns (string memory) {
                            if (value == 0) {
                                return "0x00";
                            }
                            uint256 temp = value;
                            uint256 length = 0;
                            while (temp != 0) {
                                length++;
                                temp >>= 8;
                            }
                            return toHexString(value, length);
                        }
                        /**
                         * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation with fixed length.
                         */
                        function toHexString(uint256 value, uint256 length) internal pure returns (string memory) {
                            bytes memory buffer = new bytes(2 * length + 2);
                            buffer[0] = "0";
                            buffer[1] = "x";
                            for (uint256 i = 2 * length + 1; i > 1; --i) {
                                buffer[i] = _HEX_SYMBOLS[value & 0xf];
                                value >>= 4;
                            }
                            require(value == 0, "Strings: hex length insufficient");
                            return string(buffer);
                        }
                        /**
                         * @dev Converts an `address` with fixed length of 20 bytes to its not checksummed ASCII `string` hexadecimal representation.
                         */
                        function toHexString(address addr) internal pure returns (string memory) {
                            return toHexString(uint256(uint160(addr)), _ADDRESS_LENGTH);
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    // OpenZeppelin Contracts (last updated v4.7.0) (utils/math/Math.sol)
                    pragma solidity ^0.8.0;
                    /**
                     * @dev Standard math utilities missing in the Solidity language.
                     */
                    library Math {
                        enum Rounding {
                            Down, // Toward negative infinity
                            Up, // Toward infinity
                            Zero // Toward zero
                        }
                        /**
                         * @dev Returns the largest of two numbers.
                         */
                        function max(uint256 a, uint256 b) internal pure returns (uint256) {
                            return a >= b ? a : b;
                        }
                        /**
                         * @dev Returns the smallest of two numbers.
                         */
                        function min(uint256 a, uint256 b) internal pure returns (uint256) {
                            return a < b ? a : b;
                        }
                        /**
                         * @dev Returns the average of two numbers. The result is rounded towards
                         * zero.
                         */
                        function average(uint256 a, uint256 b) internal pure returns (uint256) {
                            // (a + b) / 2 can overflow.
                            return (a & b) + (a ^ b) / 2;
                        }
                        /**
                         * @dev Returns the ceiling of the division of two numbers.
                         *
                         * This differs from standard division with `/` in that it rounds up instead
                         * of rounding down.
                         */
                        function ceilDiv(uint256 a, uint256 b) internal pure returns (uint256) {
                            // (a + b - 1) / b can overflow on addition, so we distribute.
                            return a == 0 ? 0 : (a - 1) / b + 1;
                        }
                        /**
                         * @notice Calculates floor(x * y / denominator) with full precision. Throws if result overflows a uint256 or denominator == 0
                         * @dev Original credit to Remco Bloemen under MIT license (https://xn--2-umb.com/21/muldiv)
                         * with further edits by Uniswap Labs also under MIT license.
                         */
                        function mulDiv(
                            uint256 x,
                            uint256 y,
                            uint256 denominator
                        ) internal pure returns (uint256 result) {
                            unchecked {
                                // 512-bit multiply [prod1 prod0] = x * y. Compute the product mod 2^256 and mod 2^256 - 1, then use
                                // use the Chinese Remainder Theorem to reconstruct the 512 bit result. The result is stored in two 256
                                // variables such that product = prod1 * 2^256 + prod0.
                                uint256 prod0; // Least significant 256 bits of the product
                                uint256 prod1; // Most significant 256 bits of the product
                                assembly {
                                    let mm := mulmod(x, y, not(0))
                                    prod0 := mul(x, y)
                                    prod1 := sub(sub(mm, prod0), lt(mm, prod0))
                                }
                                // Handle non-overflow cases, 256 by 256 division.
                                if (prod1 == 0) {
                                    return prod0 / denominator;
                                }
                                // Make sure the result is less than 2^256. Also prevents denominator == 0.
                                require(denominator > prod1);
                                ///////////////////////////////////////////////
                                // 512 by 256 division.
                                ///////////////////////////////////////////////
                                // Make division exact by subtracting the remainder from [prod1 prod0].
                                uint256 remainder;
                                assembly {
                                    // Compute remainder using mulmod.
                                    remainder := mulmod(x, y, denominator)
                                    // Subtract 256 bit number from 512 bit number.
                                    prod1 := sub(prod1, gt(remainder, prod0))
                                    prod0 := sub(prod0, remainder)
                                }
                                // Factor powers of two out of denominator and compute largest power of two divisor of denominator. Always >= 1.
                                // See https://cs.stackexchange.com/q/138556/92363.
                                // Does not overflow because the denominator cannot be zero at this stage in the function.
                                uint256 twos = denominator & (~denominator + 1);
                                assembly {
                                    // Divide denominator by twos.
                                    denominator := div(denominator, twos)
                                    // Divide [prod1 prod0] by twos.
                                    prod0 := div(prod0, twos)
                                    // Flip twos such that it is 2^256 / twos. If twos is zero, then it becomes one.
                                    twos := add(div(sub(0, twos), twos), 1)
                                }
                                // Shift in bits from prod1 into prod0.
                                prod0 |= prod1 * twos;
                                // Invert denominator mod 2^256. Now that denominator is an odd number, it has an inverse modulo 2^256 such
                                // that denominator * inv = 1 mod 2^256. Compute the inverse by starting with a seed that is correct for
                                // four bits. That is, denominator * inv = 1 mod 2^4.
                                uint256 inverse = (3 * denominator) ^ 2;
                                // Use the Newton-Raphson iteration to improve the precision. Thanks to Hensel's lifting lemma, this also works
                                // in modular arithmetic, doubling the correct bits in each step.
                                inverse *= 2 - denominator * inverse; // inverse mod 2^8
                                inverse *= 2 - denominator * inverse; // inverse mod 2^16
                                inverse *= 2 - denominator * inverse; // inverse mod 2^32
                                inverse *= 2 - denominator * inverse; // inverse mod 2^64
                                inverse *= 2 - denominator * inverse; // inverse mod 2^128
                                inverse *= 2 - denominator * inverse; // inverse mod 2^256
                                // Because the division is now exact we can divide by multiplying with the modular inverse of denominator.
                                // This will give us the correct result modulo 2^256. Since the preconditions guarantee that the outcome is
                                // less than 2^256, this is the final result. We don't need to compute the high bits of the result and prod1
                                // is no longer required.
                                result = prod0 * inverse;
                                return result;
                            }
                        }
                        /**
                         * @notice Calculates x * y / denominator with full precision, following the selected rounding direction.
                         */
                        function mulDiv(
                            uint256 x,
                            uint256 y,
                            uint256 denominator,
                            Rounding rounding
                        ) internal pure returns (uint256) {
                            uint256 result = mulDiv(x, y, denominator);
                            if (rounding == Rounding.Up && mulmod(x, y, denominator) > 0) {
                                result += 1;
                            }
                            return result;
                        }
                        /**
                         * @dev Returns the square root of a number. It the number is not a perfect square, the value is rounded down.
                         *
                         * Inspired by Henry S. Warren, Jr.'s "Hacker's Delight" (Chapter 11).
                         */
                        function sqrt(uint256 a) internal pure returns (uint256) {
                            if (a == 0) {
                                return 0;
                            }
                            // For our first guess, we get the biggest power of 2 which is smaller than the square root of the target.
                            // We know that the "msb" (most significant bit) of our target number `a` is a power of 2 such that we have
                            // `msb(a) <= a < 2*msb(a)`.
                            // We also know that `k`, the position of the most significant bit, is such that `msb(a) = 2**k`.
                            // This gives `2**k < a <= 2**(k+1)` → `2**(k/2) <= sqrt(a) < 2 ** (k/2+1)`.
                            // Using an algorithm similar to the msb conmputation, we are able to compute `result = 2**(k/2)` which is a
                            // good first aproximation of `sqrt(a)` with at least 1 correct bit.
                            uint256 result = 1;
                            uint256 x = a;
                            if (x >> 128 > 0) {
                                x >>= 128;
                                result <<= 64;
                            }
                            if (x >> 64 > 0) {
                                x >>= 64;
                                result <<= 32;
                            }
                            if (x >> 32 > 0) {
                                x >>= 32;
                                result <<= 16;
                            }
                            if (x >> 16 > 0) {
                                x >>= 16;
                                result <<= 8;
                            }
                            if (x >> 8 > 0) {
                                x >>= 8;
                                result <<= 4;
                            }
                            if (x >> 4 > 0) {
                                x >>= 4;
                                result <<= 2;
                            }
                            if (x >> 2 > 0) {
                                result <<= 1;
                            }
                            // At this point `result` is an estimation with one bit of precision. We know the true value is a uint128,
                            // since it is the square root of a uint256. Newton's method converges quadratically (precision doubles at
                            // every iteration). We thus need at most 7 iteration to turn our partial result with one bit of precision
                            // into the expected uint128 result.
                            unchecked {
                                result = (result + a / result) >> 1;
                                result = (result + a / result) >> 1;
                                result = (result + a / result) >> 1;
                                result = (result + a / result) >> 1;
                                result = (result + a / result) >> 1;
                                result = (result + a / result) >> 1;
                                result = (result + a / result) >> 1;
                                return min(result, a / result);
                            }
                        }
                        /**
                         * @notice Calculates sqrt(a), following the selected rounding direction.
                         */
                        function sqrt(uint256 a, Rounding rounding) internal pure returns (uint256) {
                            uint256 result = sqrt(a);
                            if (rounding == Rounding.Up && result * result < a) {
                                result += 1;
                            }
                            return result;
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    // OpenZeppelin Contracts (last updated v4.5.0) (utils/math/SignedMath.sol)
                    pragma solidity ^0.8.0;
                    /**
                     * @dev Standard signed math utilities missing in the Solidity language.
                     */
                    library SignedMath {
                        /**
                         * @dev Returns the largest of two signed numbers.
                         */
                        function max(int256 a, int256 b) internal pure returns (int256) {
                            return a >= b ? a : b;
                        }
                        /**
                         * @dev Returns the smallest of two signed numbers.
                         */
                        function min(int256 a, int256 b) internal pure returns (int256) {
                            return a < b ? a : b;
                        }
                        /**
                         * @dev Returns the average of two signed numbers without overflow.
                         * The result is rounded towards zero.
                         */
                        function average(int256 a, int256 b) internal pure returns (int256) {
                            // Formula from the book "Hacker's Delight"
                            int256 x = (a & b) + ((a ^ b) >> 1);
                            return x + (int256(uint256(x) >> 255) & (a ^ b));
                        }
                        /**
                         * @dev Returns the absolute unsigned value of a signed value.
                         */
                        function abs(int256 n) internal pure returns (uint256) {
                            unchecked {
                                // must be unchecked in order to support `n = type(int256).min`
                                return uint256(n >= 0 ? n : -n);
                            }
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    // OpenZeppelin Contracts (last updated v4.7.0) (access/Ownable.sol)
                    pragma solidity ^0.8.0;
                    import "../utils/ContextUpgradeable.sol";
                    import "../proxy/utils/Initializable.sol";
                    /**
                     * @dev Contract module which provides a basic access control mechanism, where
                     * there is an account (an owner) that can be granted exclusive access to
                     * specific functions.
                     *
                     * By default, the owner account will be the one that deploys the contract. This
                     * can later be changed with {transferOwnership}.
                     *
                     * This module is used through inheritance. It will make available the modifier
                     * `onlyOwner`, which can be applied to your functions to restrict their use to
                     * the owner.
                     */
                    abstract contract OwnableUpgradeable is Initializable, ContextUpgradeable {
                        address private _owner;
                        event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
                        /**
                         * @dev Initializes the contract setting the deployer as the initial owner.
                         */
                        function __Ownable_init() internal onlyInitializing {
                            __Ownable_init_unchained();
                        }
                        function __Ownable_init_unchained() internal onlyInitializing {
                            _transferOwnership(_msgSender());
                        }
                        /**
                         * @dev Throws if called by any account other than the owner.
                         */
                        modifier onlyOwner() {
                            _checkOwner();
                            _;
                        }
                        /**
                         * @dev Returns the address of the current owner.
                         */
                        function owner() public view virtual returns (address) {
                            return _owner;
                        }
                        /**
                         * @dev Throws if the sender is not the owner.
                         */
                        function _checkOwner() internal view virtual {
                            require(owner() == _msgSender(), "Ownable: caller is not the owner");
                        }
                        /**
                         * @dev Leaves the contract without owner. It will not be possible to call
                         * `onlyOwner` functions anymore. Can only be called by the current owner.
                         *
                         * NOTE: Renouncing ownership will leave the contract without an owner,
                         * thereby removing any functionality that is only available to the owner.
                         */
                        function renounceOwnership() public virtual onlyOwner {
                            _transferOwnership(address(0));
                        }
                        /**
                         * @dev Transfers ownership of the contract to a new account (`newOwner`).
                         * Can only be called by the current owner.
                         */
                        function transferOwnership(address newOwner) public virtual onlyOwner {
                            require(newOwner != address(0), "Ownable: new owner is the zero address");
                            _transferOwnership(newOwner);
                        }
                        /**
                         * @dev Transfers ownership of the contract to a new account (`newOwner`).
                         * Internal function without access restriction.
                         */
                        function _transferOwnership(address newOwner) internal virtual {
                            address oldOwner = _owner;
                            _owner = newOwner;
                            emit OwnershipTransferred(oldOwner, newOwner);
                        }
                        /**
                         * @dev This empty reserved space is put in place to allow future versions to add new
                         * variables without shifting down storage in the inheritance chain.
                         * See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
                         */
                        uint256[49] private __gap;
                    }
                    // SPDX-License-Identifier: MIT
                    // OpenZeppelin Contracts (last updated v4.7.0) (proxy/utils/Initializable.sol)
                    pragma solidity ^0.8.2;
                    import "../../utils/AddressUpgradeable.sol";
                    /**
                     * @dev This is a base contract to aid in writing upgradeable contracts, or any kind of contract that will be deployed
                     * behind a proxy. Since proxied contracts do not make use of a constructor, it's common to move constructor logic to an
                     * external initializer function, usually called `initialize`. It then becomes necessary to protect this initializer
                     * function so it can only be called once. The {initializer} modifier provided by this contract will have this effect.
                     *
                     * The initialization functions use a version number. Once a version number is used, it is consumed and cannot be
                     * reused. This mechanism prevents re-execution of each "step" but allows the creation of new initialization steps in
                     * case an upgrade adds a module that needs to be initialized.
                     *
                     * For example:
                     *
                     * [.hljs-theme-light.nopadding]
                     * ```
                     * contract MyToken is ERC20Upgradeable {
                     *     function initialize() initializer public {
                     *         __ERC20_init("MyToken", "MTK");
                     *     }
                     * }
                     * contract MyTokenV2 is MyToken, ERC20PermitUpgradeable {
                     *     function initializeV2() reinitializer(2) public {
                     *         __ERC20Permit_init("MyToken");
                     *     }
                     * }
                     * ```
                     *
                     * TIP: To avoid leaving the proxy in an uninitialized state, the initializer function should be called as early as
                     * possible by providing the encoded function call as the `_data` argument to {ERC1967Proxy-constructor}.
                     *
                     * CAUTION: When used with inheritance, manual care must be taken to not invoke a parent initializer twice, or to ensure
                     * that all initializers are idempotent. This is not verified automatically as constructors are by Solidity.
                     *
                     * [CAUTION]
                     * ====
                     * Avoid leaving a contract uninitialized.
                     *
                     * An uninitialized contract can be taken over by an attacker. This applies to both a proxy and its implementation
                     * contract, which may impact the proxy. To prevent the implementation contract from being used, you should invoke
                     * the {_disableInitializers} function in the constructor to automatically lock it when it is deployed:
                     *
                     * [.hljs-theme-light.nopadding]
                     * ```
                     * /// @custom:oz-upgrades-unsafe-allow constructor
                     * constructor() {
                     *     _disableInitializers();
                     * }
                     * ```
                     * ====
                     */
                    abstract contract Initializable {
                        /**
                         * @dev Indicates that the contract has been initialized.
                         * @custom:oz-retyped-from bool
                         */
                        uint8 private _initialized;
                        /**
                         * @dev Indicates that the contract is in the process of being initialized.
                         */
                        bool private _initializing;
                        /**
                         * @dev Triggered when the contract has been initialized or reinitialized.
                         */
                        event Initialized(uint8 version);
                        /**
                         * @dev A modifier that defines a protected initializer function that can be invoked at most once. In its scope,
                         * `onlyInitializing` functions can be used to initialize parent contracts. Equivalent to `reinitializer(1)`.
                         */
                        modifier initializer() {
                            bool isTopLevelCall = !_initializing;
                            require(
                                (isTopLevelCall && _initialized < 1) || (!AddressUpgradeable.isContract(address(this)) && _initialized == 1),
                                "Initializable: contract is already initialized"
                            );
                            _initialized = 1;
                            if (isTopLevelCall) {
                                _initializing = true;
                            }
                            _;
                            if (isTopLevelCall) {
                                _initializing = false;
                                emit Initialized(1);
                            }
                        }
                        /**
                         * @dev A modifier that defines a protected reinitializer function that can be invoked at most once, and only if the
                         * contract hasn't been initialized to a greater version before. In its scope, `onlyInitializing` functions can be
                         * used to initialize parent contracts.
                         *
                         * `initializer` is equivalent to `reinitializer(1)`, so a reinitializer may be used after the original
                         * initialization step. This is essential to configure modules that are added through upgrades and that require
                         * initialization.
                         *
                         * Note that versions can jump in increments greater than 1; this implies that if multiple reinitializers coexist in
                         * a contract, executing them in the right order is up to the developer or operator.
                         */
                        modifier reinitializer(uint8 version) {
                            require(!_initializing && _initialized < version, "Initializable: contract is already initialized");
                            _initialized = version;
                            _initializing = true;
                            _;
                            _initializing = false;
                            emit Initialized(version);
                        }
                        /**
                         * @dev Modifier to protect an initialization function so that it can only be invoked by functions with the
                         * {initializer} and {reinitializer} modifiers, directly or indirectly.
                         */
                        modifier onlyInitializing() {
                            require(_initializing, "Initializable: contract is not initializing");
                            _;
                        }
                        /**
                         * @dev Locks the contract, preventing any future reinitialization. This cannot be part of an initializer call.
                         * Calling this in the constructor of a contract will prevent that contract from being initialized or reinitialized
                         * to any version. It is recommended to use this to lock implementation contracts that are designed to be called
                         * through proxies.
                         */
                        function _disableInitializers() internal virtual {
                            require(!_initializing, "Initializable: contract is initializing");
                            if (_initialized < type(uint8).max) {
                                _initialized = type(uint8).max;
                                emit Initialized(type(uint8).max);
                            }
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    // OpenZeppelin Contracts (last updated v4.7.0) (utils/Address.sol)
                    pragma solidity ^0.8.1;
                    /**
                     * @dev Collection of functions related to the address type
                     */
                    library AddressUpgradeable {
                        /**
                         * @dev Returns true if `account` is a contract.
                         *
                         * [IMPORTANT]
                         * ====
                         * It is unsafe to assume that an address for which this function returns
                         * false is an externally-owned account (EOA) and not a contract.
                         *
                         * Among others, `isContract` will return false for the following
                         * types of addresses:
                         *
                         *  - an externally-owned account
                         *  - a contract in construction
                         *  - an address where a contract will be created
                         *  - an address where a contract lived, but was destroyed
                         * ====
                         *
                         * [IMPORTANT]
                         * ====
                         * You shouldn't rely on `isContract` to protect against flash loan attacks!
                         *
                         * Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets
                         * like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract
                         * constructor.
                         * ====
                         */
                        function isContract(address account) internal view returns (bool) {
                            // This method relies on extcodesize/address.code.length, which returns 0
                            // for contracts in construction, since the code is only stored at the end
                            // of the constructor execution.
                            return account.code.length > 0;
                        }
                        /**
                         * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
                         * `recipient`, forwarding all available gas and reverting on errors.
                         *
                         * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
                         * of certain opcodes, possibly making contracts go over the 2300 gas limit
                         * imposed by `transfer`, making them unable to receive funds via
                         * `transfer`. {sendValue} removes this limitation.
                         *
                         * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
                         *
                         * IMPORTANT: because control is transferred to `recipient`, care must be
                         * taken to not create reentrancy vulnerabilities. Consider using
                         * {ReentrancyGuard} or the
                         * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
                         */
                        function sendValue(address payable recipient, uint256 amount) internal {
                            require(address(this).balance >= amount, "Address: insufficient balance");
                            (bool success, ) = recipient.call{value: amount}("");
                            require(success, "Address: unable to send value, recipient may have reverted");
                        }
                        /**
                         * @dev Performs a Solidity function call using a low level `call`. A
                         * plain `call` is an unsafe replacement for a function call: use this
                         * function instead.
                         *
                         * If `target` reverts with a revert reason, it is bubbled up by this
                         * function (like regular Solidity function calls).
                         *
                         * Returns the raw returned data. To convert to the expected return value,
                         * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
                         *
                         * Requirements:
                         *
                         * - `target` must be a contract.
                         * - calling `target` with `data` must not revert.
                         *
                         * _Available since v3.1._
                         */
                        function functionCall(address target, bytes memory data) internal returns (bytes memory) {
                            return functionCall(target, data, "Address: low-level call failed");
                        }
                        /**
                         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
                         * `errorMessage` as a fallback revert reason when `target` reverts.
                         *
                         * _Available since v3.1._
                         */
                        function functionCall(
                            address target,
                            bytes memory data,
                            string memory errorMessage
                        ) internal returns (bytes memory) {
                            return functionCallWithValue(target, data, 0, errorMessage);
                        }
                        /**
                         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
                         * but also transferring `value` wei to `target`.
                         *
                         * Requirements:
                         *
                         * - the calling contract must have an ETH balance of at least `value`.
                         * - the called Solidity function must be `payable`.
                         *
                         * _Available since v3.1._
                         */
                        function functionCallWithValue(
                            address target,
                            bytes memory data,
                            uint256 value
                        ) internal returns (bytes memory) {
                            return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
                        }
                        /**
                         * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
                         * with `errorMessage` as a fallback revert reason when `target` reverts.
                         *
                         * _Available since v3.1._
                         */
                        function functionCallWithValue(
                            address target,
                            bytes memory data,
                            uint256 value,
                            string memory errorMessage
                        ) internal returns (bytes memory) {
                            require(address(this).balance >= value, "Address: insufficient balance for call");
                            require(isContract(target), "Address: call to non-contract");
                            (bool success, bytes memory returndata) = target.call{value: value}(data);
                            return verifyCallResult(success, returndata, errorMessage);
                        }
                        /**
                         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
                         * but performing a static call.
                         *
                         * _Available since v3.3._
                         */
                        function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
                            return functionStaticCall(target, data, "Address: low-level static call failed");
                        }
                        /**
                         * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
                         * but performing a static call.
                         *
                         * _Available since v3.3._
                         */
                        function functionStaticCall(
                            address target,
                            bytes memory data,
                            string memory errorMessage
                        ) internal view returns (bytes memory) {
                            require(isContract(target), "Address: static call to non-contract");
                            (bool success, bytes memory returndata) = target.staticcall(data);
                            return verifyCallResult(success, returndata, errorMessage);
                        }
                        /**
                         * @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the
                         * revert reason using the provided one.
                         *
                         * _Available since v4.3._
                         */
                        function verifyCallResult(
                            bool success,
                            bytes memory returndata,
                            string memory errorMessage
                        ) internal pure returns (bytes memory) {
                            if (success) {
                                return returndata;
                            } else {
                                // Look for revert reason and bubble it up if present
                                if (returndata.length > 0) {
                                    // The easiest way to bubble the revert reason is using memory via assembly
                                    /// @solidity memory-safe-assembly
                                    assembly {
                                        let returndata_size := mload(returndata)
                                        revert(add(32, returndata), returndata_size)
                                    }
                                } else {
                                    revert(errorMessage);
                                }
                            }
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    // OpenZeppelin Contracts v4.4.1 (utils/Context.sol)
                    pragma solidity ^0.8.0;
                    import "../proxy/utils/Initializable.sol";
                    /**
                     * @dev Provides information about the current execution context, including the
                     * sender of the transaction and its data. While these are generally available
                     * via msg.sender and msg.data, they should not be accessed in such a direct
                     * manner, since when dealing with meta-transactions the account sending and
                     * paying for execution may not be the actual sender (as far as an application
                     * is concerned).
                     *
                     * This contract is only required for intermediate, library-like contracts.
                     */
                    abstract contract ContextUpgradeable is Initializable {
                        function __Context_init() internal onlyInitializing {
                        }
                        function __Context_init_unchained() internal onlyInitializing {
                        }
                        function _msgSender() internal view virtual returns (address) {
                            return msg.sender;
                        }
                        function _msgData() internal view virtual returns (bytes calldata) {
                            return msg.data;
                        }
                        /**
                         * @dev This empty reserved space is put in place to allow future versions to add new
                         * variables without shifting down storage in the inheritance chain.
                         * See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
                         */
                        uint256[50] private __gap;
                    }
                    // SPDX-License-Identifier: MIT
                    pragma solidity >=0.8.0;
                    /// @notice Arithmetic library with operations for fixed-point numbers.
                    /// @author Solmate (https://github.com/Rari-Capital/solmate/blob/main/src/utils/FixedPointMathLib.sol)
                    library FixedPointMathLib {
                        /*//////////////////////////////////////////////////////////////
                                        SIMPLIFIED FIXED POINT OPERATIONS
                        //////////////////////////////////////////////////////////////*/
                        uint256 internal constant WAD = 1e18; // The scalar of ETH and most ERC20s.
                        function mulWadDown(uint256 x, uint256 y) internal pure returns (uint256) {
                            return mulDivDown(x, y, WAD); // Equivalent to (x * y) / WAD rounded down.
                        }
                        function mulWadUp(uint256 x, uint256 y) internal pure returns (uint256) {
                            return mulDivUp(x, y, WAD); // Equivalent to (x * y) / WAD rounded up.
                        }
                        function divWadDown(uint256 x, uint256 y) internal pure returns (uint256) {
                            return mulDivDown(x, WAD, y); // Equivalent to (x * WAD) / y rounded down.
                        }
                        function divWadUp(uint256 x, uint256 y) internal pure returns (uint256) {
                            return mulDivUp(x, WAD, y); // Equivalent to (x * WAD) / y rounded up.
                        }
                        function powWad(int256 x, int256 y) internal pure returns (int256) {
                            // Equivalent to x to the power of y because x ** y = (e ** ln(x)) ** y = e ** (ln(x) * y)
                            return expWad((lnWad(x) * y) / int256(WAD)); // Using ln(x) means x must be greater than 0.
                        }
                        function expWad(int256 x) internal pure returns (int256 r) {
                            unchecked {
                                // When the result is < 0.5 we return zero. This happens when
                                // x <= floor(log(0.5e18) * 1e18) ~ -42e18
                                if (x <= -42139678854452767551) return 0;
                                // When the result is > (2**255 - 1) / 1e18 we can not represent it as an
                                // int. This happens when x >= floor(log((2**255 - 1) / 1e18) * 1e18) ~ 135.
                                if (x >= 135305999368893231589) revert("EXP_OVERFLOW");
                                // x is now in the range (-42, 136) * 1e18. Convert to (-42, 136) * 2**96
                                // for more intermediate precision and a binary basis. This base conversion
                                // is a multiplication by 1e18 / 2**96 = 5**18 / 2**78.
                                x = (x << 78) / 5**18;
                                // Reduce range of x to (-½ ln 2, ½ ln 2) * 2**96 by factoring out powers
                                // of two such that exp(x) = exp(x') * 2**k, where k is an integer.
                                // Solving this gives k = round(x / log(2)) and x' = x - k * log(2).
                                int256 k = ((x << 96) / 54916777467707473351141471128 + 2**95) >> 96;
                                x = x - k * 54916777467707473351141471128;
                                // k is in the range [-61, 195].
                                // Evaluate using a (6, 7)-term rational approximation.
                                // p is made monic, we'll multiply by a scale factor later.
                                int256 y = x + 1346386616545796478920950773328;
                                y = ((y * x) >> 96) + 57155421227552351082224309758442;
                                int256 p = y + x - 94201549194550492254356042504812;
                                p = ((p * y) >> 96) + 28719021644029726153956944680412240;
                                p = p * x + (4385272521454847904659076985693276 << 96);
                                // We leave p in 2**192 basis so we don't need to scale it back up for the division.
                                int256 q = x - 2855989394907223263936484059900;
                                q = ((q * x) >> 96) + 50020603652535783019961831881945;
                                q = ((q * x) >> 96) - 533845033583426703283633433725380;
                                q = ((q * x) >> 96) + 3604857256930695427073651918091429;
                                q = ((q * x) >> 96) - 14423608567350463180887372962807573;
                                q = ((q * x) >> 96) + 26449188498355588339934803723976023;
                                assembly {
                                    // Div in assembly because solidity adds a zero check despite the unchecked.
                                    // The q polynomial won't have zeros in the domain as all its roots are complex.
                                    // No scaling is necessary because p is already 2**96 too large.
                                    r := sdiv(p, q)
                                }
                                // r should be in the range (0.09, 0.25) * 2**96.
                                // We now need to multiply r by:
                                // * the scale factor s = ~6.031367120.
                                // * the 2**k factor from the range reduction.
                                // * the 1e18 / 2**96 factor for base conversion.
                                // We do this all at once, with an intermediate result in 2**213
                                // basis, so the final right shift is always by a positive amount.
                                r = int256((uint256(r) * 3822833074963236453042738258902158003155416615667) >> uint256(195 - k));
                            }
                        }
                        function lnWad(int256 x) internal pure returns (int256 r) {
                            unchecked {
                                require(x > 0, "UNDEFINED");
                                // We want to convert x from 10**18 fixed point to 2**96 fixed point.
                                // We do this by multiplying by 2**96 / 10**18. But since
                                // ln(x * C) = ln(x) + ln(C), we can simply do nothing here
                                // and add ln(2**96 / 10**18) at the end.
                                // Reduce range of x to (1, 2) * 2**96
                                // ln(2^k * x) = k * ln(2) + ln(x)
                                int256 k = int256(log2(uint256(x))) - 96;
                                x <<= uint256(159 - k);
                                x = int256(uint256(x) >> 159);
                                // Evaluate using a (8, 8)-term rational approximation.
                                // p is made monic, we will multiply by a scale factor later.
                                int256 p = x + 3273285459638523848632254066296;
                                p = ((p * x) >> 96) + 24828157081833163892658089445524;
                                p = ((p * x) >> 96) + 43456485725739037958740375743393;
                                p = ((p * x) >> 96) - 11111509109440967052023855526967;
                                p = ((p * x) >> 96) - 45023709667254063763336534515857;
                                p = ((p * x) >> 96) - 14706773417378608786704636184526;
                                p = p * x - (795164235651350426258249787498 << 96);
                                // We leave p in 2**192 basis so we don't need to scale it back up for the division.
                                // q is monic by convention.
                                int256 q = x + 5573035233440673466300451813936;
                                q = ((q * x) >> 96) + 71694874799317883764090561454958;
                                q = ((q * x) >> 96) + 283447036172924575727196451306956;
                                q = ((q * x) >> 96) + 401686690394027663651624208769553;
                                q = ((q * x) >> 96) + 204048457590392012362485061816622;
                                q = ((q * x) >> 96) + 31853899698501571402653359427138;
                                q = ((q * x) >> 96) + 909429971244387300277376558375;
                                assembly {
                                    // Div in assembly because solidity adds a zero check despite the unchecked.
                                    // The q polynomial is known not to have zeros in the domain.
                                    // No scaling required because p is already 2**96 too large.
                                    r := sdiv(p, q)
                                }
                                // r is in the range (0, 0.125) * 2**96
                                // Finalization, we need to:
                                // * multiply by the scale factor s = 5.549…
                                // * add ln(2**96 / 10**18)
                                // * add k * ln(2)
                                // * multiply by 10**18 / 2**96 = 5**18 >> 78
                                // mul s * 5e18 * 2**96, base is now 5**18 * 2**192
                                r *= 1677202110996718588342820967067443963516166;
                                // add ln(2) * k * 5e18 * 2**192
                                r += 16597577552685614221487285958193947469193820559219878177908093499208371 * k;
                                // add ln(2**96 / 10**18) * 5e18 * 2**192
                                r += 600920179829731861736702779321621459595472258049074101567377883020018308;
                                // base conversion: mul 2**18 / 2**192
                                r >>= 174;
                            }
                        }
                        /*//////////////////////////////////////////////////////////////
                                        LOW LEVEL FIXED POINT OPERATIONS
                        //////////////////////////////////////////////////////////////*/
                        function mulDivDown(
                            uint256 x,
                            uint256 y,
                            uint256 denominator
                        ) internal pure returns (uint256 z) {
                            assembly {
                                // Store x * y in z for now.
                                z := mul(x, y)
                                // Equivalent to require(denominator != 0 && (x == 0 || (x * y) / x == y))
                                if iszero(and(iszero(iszero(denominator)), or(iszero(x), eq(div(z, x), y)))) {
                                    revert(0, 0)
                                }
                                // Divide z by the denominator.
                                z := div(z, denominator)
                            }
                        }
                        function mulDivUp(
                            uint256 x,
                            uint256 y,
                            uint256 denominator
                        ) internal pure returns (uint256 z) {
                            assembly {
                                // Store x * y in z for now.
                                z := mul(x, y)
                                // Equivalent to require(denominator != 0 && (x == 0 || (x * y) / x == y))
                                if iszero(and(iszero(iszero(denominator)), or(iszero(x), eq(div(z, x), y)))) {
                                    revert(0, 0)
                                }
                                // First, divide z - 1 by the denominator and add 1.
                                // We allow z - 1 to underflow if z is 0, because we multiply the
                                // end result by 0 if z is zero, ensuring we return 0 if z is zero.
                                z := mul(iszero(iszero(z)), add(div(sub(z, 1), denominator), 1))
                            }
                        }
                        function rpow(
                            uint256 x,
                            uint256 n,
                            uint256 scalar
                        ) internal pure returns (uint256 z) {
                            assembly {
                                switch x
                                case 0 {
                                    switch n
                                    case 0 {
                                        // 0 ** 0 = 1
                                        z := scalar
                                    }
                                    default {
                                        // 0 ** n = 0
                                        z := 0
                                    }
                                }
                                default {
                                    switch mod(n, 2)
                                    case 0 {
                                        // If n is even, store scalar in z for now.
                                        z := scalar
                                    }
                                    default {
                                        // If n is odd, store x in z for now.
                                        z := x
                                    }
                                    // Shifting right by 1 is like dividing by 2.
                                    let half := shr(1, scalar)
                                    for {
                                        // Shift n right by 1 before looping to halve it.
                                        n := shr(1, n)
                                    } n {
                                        // Shift n right by 1 each iteration to halve it.
                                        n := shr(1, n)
                                    } {
                                        // Revert immediately if x ** 2 would overflow.
                                        // Equivalent to iszero(eq(div(xx, x), x)) here.
                                        if shr(128, x) {
                                            revert(0, 0)
                                        }
                                        // Store x squared.
                                        let xx := mul(x, x)
                                        // Round to the nearest number.
                                        let xxRound := add(xx, half)
                                        // Revert if xx + half overflowed.
                                        if lt(xxRound, xx) {
                                            revert(0, 0)
                                        }
                                        // Set x to scaled xxRound.
                                        x := div(xxRound, scalar)
                                        // If n is even:
                                        if mod(n, 2) {
                                            // Compute z * x.
                                            let zx := mul(z, x)
                                            // If z * x overflowed:
                                            if iszero(eq(div(zx, x), z)) {
                                                // Revert if x is non-zero.
                                                if iszero(iszero(x)) {
                                                    revert(0, 0)
                                                }
                                            }
                                            // Round to the nearest number.
                                            let zxRound := add(zx, half)
                                            // Revert if zx + half overflowed.
                                            if lt(zxRound, zx) {
                                                revert(0, 0)
                                            }
                                            // Return properly scaled zxRound.
                                            z := div(zxRound, scalar)
                                        }
                                    }
                                }
                            }
                        }
                        /*//////////////////////////////////////////////////////////////
                                            GENERAL NUMBER UTILITIES
                        //////////////////////////////////////////////////////////////*/
                        function sqrt(uint256 x) internal pure returns (uint256 z) {
                            assembly {
                                let y := x // We start y at x, which will help us make our initial estimate.
                                z := 181 // The "correct" value is 1, but this saves a multiplication later.
                                // This segment is to get a reasonable initial estimate for the Babylonian method. With a bad
                                // start, the correct # of bits increases ~linearly each iteration instead of ~quadratically.
                                // We check y >= 2^(k + 8) but shift right by k bits
                                // each branch to ensure that if x >= 256, then y >= 256.
                                if iszero(lt(y, 0x10000000000000000000000000000000000)) {
                                    y := shr(128, y)
                                    z := shl(64, z)
                                }
                                if iszero(lt(y, 0x1000000000000000000)) {
                                    y := shr(64, y)
                                    z := shl(32, z)
                                }
                                if iszero(lt(y, 0x10000000000)) {
                                    y := shr(32, y)
                                    z := shl(16, z)
                                }
                                if iszero(lt(y, 0x1000000)) {
                                    y := shr(16, y)
                                    z := shl(8, z)
                                }
                                // Goal was to get z*z*y within a small factor of x. More iterations could
                                // get y in a tighter range. Currently, we will have y in [256, 256*2^16).
                                // We ensured y >= 256 so that the relative difference between y and y+1 is small.
                                // That's not possible if x < 256 but we can just verify those cases exhaustively.
                                // Now, z*z*y <= x < z*z*(y+1), and y <= 2^(16+8), and either y >= 256, or x < 256.
                                // Correctness can be checked exhaustively for x < 256, so we assume y >= 256.
                                // Then z*sqrt(y) is within sqrt(257)/sqrt(256) of sqrt(x), or about 20bps.
                                // For s in the range [1/256, 256], the estimate f(s) = (181/1024) * (s+1) is in the range
                                // (1/2.84 * sqrt(s), 2.84 * sqrt(s)), with largest error when s = 1 and when s = 256 or 1/256.
                                // Since y is in [256, 256*2^16), let a = y/65536, so that a is in [1/256, 256). Then we can estimate
                                // sqrt(y) using sqrt(65536) * 181/1024 * (a + 1) = 181/4 * (y + 65536)/65536 = 181 * (y + 65536)/2^18.
                                // There is no overflow risk here since y < 2^136 after the first branch above.
                                z := shr(18, mul(z, add(y, 65536))) // A mul() is saved from starting z at 181.
                                // Given the worst case multiplicative error of 2.84 above, 7 iterations should be enough.
                                z := shr(1, add(z, div(x, z)))
                                z := shr(1, add(z, div(x, z)))
                                z := shr(1, add(z, div(x, z)))
                                z := shr(1, add(z, div(x, z)))
                                z := shr(1, add(z, div(x, z)))
                                z := shr(1, add(z, div(x, z)))
                                z := shr(1, add(z, div(x, z)))
                                // If x+1 is a perfect square, the Babylonian method cycles between
                                // floor(sqrt(x)) and ceil(sqrt(x)). This statement ensures we return floor.
                                // See: https://en.wikipedia.org/wiki/Integer_square_root#Using_only_integer_division
                                // Since the ceil is rare, we save gas on the assignment and repeat division in the rare case.
                                // If you don't care whether the floor or ceil square root is returned, you can remove this statement.
                                z := sub(z, lt(div(x, z), z))
                            }
                        }
                        function log2(uint256 x) internal pure returns (uint256 r) {
                            require(x > 0, "UNDEFINED");
                            assembly {
                                r := shl(7, lt(0xffffffffffffffffffffffffffffffff, x))
                                r := or(r, shl(6, lt(0xffffffffffffffff, shr(r, x))))
                                r := or(r, shl(5, lt(0xffffffff, shr(r, x))))
                                r := or(r, shl(4, lt(0xffff, shr(r, x))))
                                r := or(r, shl(3, lt(0xff, shr(r, x))))
                                r := or(r, shl(2, lt(0xf, shr(r, x))))
                                r := or(r, shl(1, lt(0x3, shr(r, x))))
                                r := or(r, lt(0x1, shr(r, x)))
                            }
                        }
                    }
                    

                    File 10 of 11: OptimismPortal
                    // SPDX-License-Identifier: MIT
                    pragma solidity 0.8.15;
                    import { Initializable } from "@openzeppelin/contracts/proxy/utils/Initializable.sol";
                    import { SafeCall } from "../libraries/SafeCall.sol";
                    import { L2OutputOracle } from "./L2OutputOracle.sol";
                    import { SystemConfig } from "./SystemConfig.sol";
                    import { Constants } from "../libraries/Constants.sol";
                    import { Types } from "../libraries/Types.sol";
                    import { Hashing } from "../libraries/Hashing.sol";
                    import { SecureMerkleTrie } from "../libraries/trie/SecureMerkleTrie.sol";
                    import { AddressAliasHelper } from "../vendor/AddressAliasHelper.sol";
                    import { ResourceMetering } from "./ResourceMetering.sol";
                    import { Semver } from "../universal/Semver.sol";
                    /// @custom:proxied
                    /// @title OptimismPortal
                    /// @notice The OptimismPortal is a low-level contract responsible for passing messages between L1
                    ///         and L2. Messages sent directly to the OptimismPortal have no form of replayability.
                    ///         Users are encouraged to use the L1CrossDomainMessenger for a higher-level interface.
                    contract OptimismPortal is Initializable, ResourceMetering, Semver {
                        /// @notice Represents a proven withdrawal.
                        /// @custom:field outputRoot    Root of the L2 output this was proven against.
                        /// @custom:field timestamp     Timestamp at whcih the withdrawal was proven.
                        /// @custom:field l2OutputIndex Index of the output this was proven against.
                        struct ProvenWithdrawal {
                            bytes32 outputRoot;
                            uint128 timestamp;
                            uint128 l2OutputIndex;
                        }
                        /// @notice Version of the deposit event.
                        uint256 internal constant DEPOSIT_VERSION = 0;
                        /// @notice The L2 gas limit set when eth is deposited using the receive() function.
                        uint64 internal constant RECEIVE_DEFAULT_GAS_LIMIT = 100_000;
                        /// @notice Address of the L2OutputOracle contract.
                        L2OutputOracle public immutable L2_ORACLE;
                        /// @notice Address of the SystemConfig contract.
                        SystemConfig public immutable SYSTEM_CONFIG;
                        /// @notice Address that has the ability to pause and unpause withdrawals.
                        address public immutable GUARDIAN;
                        /// @notice Address of the L2 account which initiated a withdrawal in this transaction.
                        ///         If the of this variable is the default L2 sender address, then we are NOT inside of
                        ///         a call to finalizeWithdrawalTransaction.
                        address public l2Sender;
                        /// @notice A list of withdrawal hashes which have been successfully finalized.
                        mapping(bytes32 => bool) public finalizedWithdrawals;
                        /// @notice A mapping of withdrawal hashes to `ProvenWithdrawal` data.
                        mapping(bytes32 => ProvenWithdrawal) public provenWithdrawals;
                        /// @notice Determines if cross domain messaging is paused.
                        ///         When set to true, withdrawals are paused.
                        ///         This may be removed in the future.
                        bool public paused;
                        /// @notice Emitted when a transaction is deposited from L1 to L2.
                        ///         The parameters of this event are read by the rollup node and used to derive deposit
                        ///         transactions on L2.
                        /// @param from       Address that triggered the deposit transaction.
                        /// @param to         Address that the deposit transaction is directed to.
                        /// @param version    Version of this deposit transaction event.
                        /// @param opaqueData ABI encoded deposit data to be parsed off-chain.
                        event TransactionDeposited(
                            address indexed from,
                            address indexed to,
                            uint256 indexed version,
                            bytes opaqueData
                        );
                        /// @notice Emitted when a withdrawal transaction is proven.
                        /// @param withdrawalHash Hash of the withdrawal transaction.
                        /// @param from           Address that triggered the withdrawal transaction.
                        /// @param to             Address that the withdrawal transaction is directed to.
                        event WithdrawalProven(
                            bytes32 indexed withdrawalHash,
                            address indexed from,
                            address indexed to
                        );
                        /// @notice Emitted when a withdrawal transaction is finalized.
                        /// @param withdrawalHash Hash of the withdrawal transaction.
                        /// @param success        Whether the withdrawal transaction was successful.
                        event WithdrawalFinalized(bytes32 indexed withdrawalHash, bool success);
                        /// @notice Emitted when the pause is triggered.
                        /// @param account Address of the account triggering the pause.
                        event Paused(address account);
                        /// @notice Emitted when the pause is lifted.
                        /// @param account Address of the account triggering the unpause.
                        event Unpaused(address account);
                        /// @notice Reverts when paused.
                        modifier whenNotPaused() {
                            require(paused == false, "OptimismPortal: paused");
                            _;
                        }
                        /// @custom:semver 1.7.2
                        /// @notice Constructs the OptimismPortal contract.
                        /// @param _l2Oracle Address of the L2OutputOracle contract.
                        /// @param _guardian Address that can pause withdrawals.
                        /// @param _paused Sets the contract's pausability state.
                        /// @param _config Address of the SystemConfig contract.
                        constructor(
                            L2OutputOracle _l2Oracle,
                            address _guardian,
                            bool _paused,
                            SystemConfig _config
                        ) Semver(1, 7, 2) {
                            L2_ORACLE = _l2Oracle;
                            GUARDIAN = _guardian;
                            SYSTEM_CONFIG = _config;
                            initialize(_paused);
                        }
                        /// @notice Initializer.
                        function initialize(bool _paused) public initializer {
                            l2Sender = Constants.DEFAULT_L2_SENDER;
                            paused = _paused;
                            __ResourceMetering_init();
                        }
                        /// @notice Pauses withdrawals.
                        function pause() external {
                            require(msg.sender == GUARDIAN, "OptimismPortal: only guardian can pause");
                            paused = true;
                            emit Paused(msg.sender);
                        }
                        /// @notice Unpauses withdrawals.
                        function unpause() external {
                            require(msg.sender == GUARDIAN, "OptimismPortal: only guardian can unpause");
                            paused = false;
                            emit Unpaused(msg.sender);
                        }
                        /// @notice Computes the minimum gas limit for a deposit.
                        ///         The minimum gas limit linearly increases based on the size of the calldata.
                        ///         This is to prevent users from creating L2 resource usage without paying for it.
                        ///         This function can be used when interacting with the portal to ensure forwards
                        ///         compatibility.
                        /// @param _byteCount Number of bytes in the calldata.
                        /// @return The minimum gas limit for a deposit.
                        function minimumGasLimit(uint64 _byteCount) public pure returns (uint64) {
                            return _byteCount * 16 + 21000;
                        }
                        /// @notice Accepts value so that users can send ETH directly to this contract and have the
                        ///         funds be deposited to their address on L2. This is intended as a convenience
                        ///         function for EOAs. Contracts should call the depositTransaction() function directly
                        ///         otherwise any deposited funds will be lost due to address aliasing.
                        // solhint-disable-next-line ordering
                        receive() external payable {
                            depositTransaction(msg.sender, msg.value, RECEIVE_DEFAULT_GAS_LIMIT, false, bytes(""));
                        }
                        /// @notice Accepts ETH value without triggering a deposit to L2.
                        ///         This function mainly exists for the sake of the migration between the legacy
                        ///         Optimism system and Bedrock.
                        function donateETH() external payable {
                            // Intentionally empty.
                        }
                        /// @notice Getter for the resource config.
                        ///         Used internally by the ResourceMetering contract.
                        ///         The SystemConfig is the source of truth for the resource config.
                        /// @return ResourceMetering ResourceConfig
                        function _resourceConfig()
                            internal
                            view
                            override
                            returns (ResourceMetering.ResourceConfig memory)
                        {
                            return SYSTEM_CONFIG.resourceConfig();
                        }
                        /// @notice Proves a withdrawal transaction.
                        /// @param _tx              Withdrawal transaction to finalize.
                        /// @param _l2OutputIndex   L2 output index to prove against.
                        /// @param _outputRootProof Inclusion proof of the L2ToL1MessagePasser contract's storage root.
                        /// @param _withdrawalProof Inclusion proof of the withdrawal in L2ToL1MessagePasser contract.
                        function proveWithdrawalTransaction(
                            Types.WithdrawalTransaction memory _tx,
                            uint256 _l2OutputIndex,
                            Types.OutputRootProof calldata _outputRootProof,
                            bytes[] calldata _withdrawalProof
                        ) external whenNotPaused {
                            // Prevent users from creating a deposit transaction where this address is the message
                            // sender on L2. Because this is checked here, we do not need to check again in
                            // `finalizeWithdrawalTransaction`.
                            require(
                                _tx.target != address(this),
                                "OptimismPortal: you cannot send messages to the portal contract"
                            );
                            // Get the output root and load onto the stack to prevent multiple mloads. This will
                            // revert if there is no output root for the given block number.
                            bytes32 outputRoot = L2_ORACLE.getL2Output(_l2OutputIndex).outputRoot;
                            // Verify that the output root can be generated with the elements in the proof.
                            require(
                                outputRoot == Hashing.hashOutputRootProof(_outputRootProof),
                                "OptimismPortal: invalid output root proof"
                            );
                            // Load the ProvenWithdrawal into memory, using the withdrawal hash as a unique identifier.
                            bytes32 withdrawalHash = Hashing.hashWithdrawal(_tx);
                            ProvenWithdrawal memory provenWithdrawal = provenWithdrawals[withdrawalHash];
                            // We generally want to prevent users from proving the same withdrawal multiple times
                            // because each successive proof will update the timestamp. A malicious user can take
                            // advantage of this to prevent other users from finalizing their withdrawal. However,
                            // since withdrawals are proven before an output root is finalized, we need to allow users
                            // to re-prove their withdrawal only in the case that the output root for their specified
                            // output index has been updated.
                            require(
                                provenWithdrawal.timestamp == 0 ||
                                    L2_ORACLE.getL2Output(provenWithdrawal.l2OutputIndex).outputRoot !=
                                    provenWithdrawal.outputRoot,
                                "OptimismPortal: withdrawal hash has already been proven"
                            );
                            // Compute the storage slot of the withdrawal hash in the L2ToL1MessagePasser contract.
                            // Refer to the Solidity documentation for more information on how storage layouts are
                            // computed for mappings.
                            bytes32 storageKey = keccak256(
                                abi.encode(
                                    withdrawalHash,
                                    uint256(0) // The withdrawals mapping is at the first slot in the layout.
                                )
                            );
                            // Verify that the hash of this withdrawal was stored in the L2toL1MessagePasser contract
                            // on L2. If this is true, under the assumption that the SecureMerkleTrie does not have
                            // bugs, then we know that this withdrawal was actually triggered on L2 and can therefore
                            // be relayed on L1.
                            require(
                                SecureMerkleTrie.verifyInclusionProof(
                                    abi.encode(storageKey),
                                    hex"01",
                                    _withdrawalProof,
                                    _outputRootProof.messagePasserStorageRoot
                                ),
                                "OptimismPortal: invalid withdrawal inclusion proof"
                            );
                            // Designate the withdrawalHash as proven by storing the `outputRoot`, `timestamp`, and
                            // `l2BlockNumber` in the `provenWithdrawals` mapping. A `withdrawalHash` can only be
                            // proven once unless it is submitted again with a different outputRoot.
                            provenWithdrawals[withdrawalHash] = ProvenWithdrawal({
                                outputRoot: outputRoot,
                                timestamp: uint128(block.timestamp),
                                l2OutputIndex: uint128(_l2OutputIndex)
                            });
                            // Emit a `WithdrawalProven` event.
                            emit WithdrawalProven(withdrawalHash, _tx.sender, _tx.target);
                        }
                        /// @notice Finalizes a withdrawal transaction.
                        /// @param _tx Withdrawal transaction to finalize.
                        function finalizeWithdrawalTransaction(Types.WithdrawalTransaction memory _tx)
                            external
                            whenNotPaused
                        {
                            // Make sure that the l2Sender has not yet been set. The l2Sender is set to a value other
                            // than the default value when a withdrawal transaction is being finalized. This check is
                            // a defacto reentrancy guard.
                            require(
                                l2Sender == Constants.DEFAULT_L2_SENDER,
                                "OptimismPortal: can only trigger one withdrawal per transaction"
                            );
                            // Grab the proven withdrawal from the `provenWithdrawals` map.
                            bytes32 withdrawalHash = Hashing.hashWithdrawal(_tx);
                            ProvenWithdrawal memory provenWithdrawal = provenWithdrawals[withdrawalHash];
                            // A withdrawal can only be finalized if it has been proven. We know that a withdrawal has
                            // been proven at least once when its timestamp is non-zero. Unproven withdrawals will have
                            // a timestamp of zero.
                            require(
                                provenWithdrawal.timestamp != 0,
                                "OptimismPortal: withdrawal has not been proven yet"
                            );
                            // As a sanity check, we make sure that the proven withdrawal's timestamp is greater than
                            // starting timestamp inside the L2OutputOracle. Not strictly necessary but extra layer of
                            // safety against weird bugs in the proving step.
                            require(
                                provenWithdrawal.timestamp >= L2_ORACLE.startingTimestamp(),
                                "OptimismPortal: withdrawal timestamp less than L2 Oracle starting timestamp"
                            );
                            // A proven withdrawal must wait at least the finalization period before it can be
                            // finalized. This waiting period can elapse in parallel with the waiting period for the
                            // output the withdrawal was proven against. In effect, this means that the minimum
                            // withdrawal time is proposal submission time + finalization period.
                            require(
                                _isFinalizationPeriodElapsed(provenWithdrawal.timestamp),
                                "OptimismPortal: proven withdrawal finalization period has not elapsed"
                            );
                            // Grab the OutputProposal from the L2OutputOracle, will revert if the output that
                            // corresponds to the given index has not been proposed yet.
                            Types.OutputProposal memory proposal = L2_ORACLE.getL2Output(
                                provenWithdrawal.l2OutputIndex
                            );
                            // Check that the output root that was used to prove the withdrawal is the same as the
                            // current output root for the given output index. An output root may change if it is
                            // deleted by the challenger address and then re-proposed.
                            require(
                                proposal.outputRoot == provenWithdrawal.outputRoot,
                                "OptimismPortal: output root proven is not the same as current output root"
                            );
                            // Check that the output proposal has also been finalized.
                            require(
                                _isFinalizationPeriodElapsed(proposal.timestamp),
                                "OptimismPortal: output proposal finalization period has not elapsed"
                            );
                            // Check that this withdrawal has not already been finalized, this is replay protection.
                            require(
                                finalizedWithdrawals[withdrawalHash] == false,
                                "OptimismPortal: withdrawal has already been finalized"
                            );
                            // Mark the withdrawal as finalized so it can't be replayed.
                            finalizedWithdrawals[withdrawalHash] = true;
                            // Set the l2Sender so contracts know who triggered this withdrawal on L2.
                            l2Sender = _tx.sender;
                            // Trigger the call to the target contract. We use a custom low level method
                            // SafeCall.callWithMinGas to ensure two key properties
                            //   1. Target contracts cannot force this call to run out of gas by returning a very large
                            //      amount of data (and this is OK because we don't care about the returndata here).
                            //   2. The amount of gas provided to the execution context of the target is at least the
                            //      gas limit specified by the user. If there is not enough gas in the current context
                            //      to accomplish this, `callWithMinGas` will revert.
                            bool success = SafeCall.callWithMinGas(_tx.target, _tx.gasLimit, _tx.value, _tx.data);
                            // Reset the l2Sender back to the default value.
                            l2Sender = Constants.DEFAULT_L2_SENDER;
                            // All withdrawals are immediately finalized. Replayability can
                            // be achieved through contracts built on top of this contract
                            emit WithdrawalFinalized(withdrawalHash, success);
                            // Reverting here is useful for determining the exact gas cost to successfully execute the
                            // sub call to the target contract if the minimum gas limit specified by the user would not
                            // be sufficient to execute the sub call.
                            if (success == false && tx.origin == Constants.ESTIMATION_ADDRESS) {
                                revert("OptimismPortal: withdrawal failed");
                            }
                        }
                        /// @notice Accepts deposits of ETH and data, and emits a TransactionDeposited event for use in
                        ///         deriving deposit transactions. Note that if a deposit is made by a contract, its
                        ///         address will be aliased when retrieved using `tx.origin` or `msg.sender`. Consider
                        ///         using the CrossDomainMessenger contracts for a simpler developer experience.
                        /// @param _to         Target address on L2.
                        /// @param _value      ETH value to send to the recipient.
                        /// @param _gasLimit   Amount of L2 gas to purchase by burning gas on L1.
                        /// @param _isCreation Whether or not the transaction is a contract creation.
                        /// @param _data       Data to trigger the recipient with.
                        function depositTransaction(
                            address _to,
                            uint256 _value,
                            uint64 _gasLimit,
                            bool _isCreation,
                            bytes memory _data
                        ) public payable metered(_gasLimit) {
                            // Just to be safe, make sure that people specify address(0) as the target when doing
                            // contract creations.
                            if (_isCreation) {
                                require(
                                    _to == address(0),
                                    "OptimismPortal: must send to address(0) when creating a contract"
                                );
                            }
                            // Prevent depositing transactions that have too small of a gas limit. Users should pay
                            // more for more resource usage.
                            require(
                                _gasLimit >= minimumGasLimit(uint64(_data.length)),
                                "OptimismPortal: gas limit too small"
                            );
                            // Prevent the creation of deposit transactions that have too much calldata. This gives an
                            // upper limit on the size of unsafe blocks over the p2p network. 120kb is chosen to ensure
                            // that the transaction can fit into the p2p network policy of 128kb even though deposit
                            // transactions are not gossipped over the p2p network.
                            require(_data.length <= 120_000, "OptimismPortal: data too large");
                            // Transform the from-address to its alias if the caller is a contract.
                            address from = msg.sender;
                            if (msg.sender != tx.origin) {
                                from = AddressAliasHelper.applyL1ToL2Alias(msg.sender);
                            }
                            // Compute the opaque data that will be emitted as part of the TransactionDeposited event.
                            // We use opaque data so that we can update the TransactionDeposited event in the future
                            // without breaking the current interface.
                            bytes memory opaqueData = abi.encodePacked(
                                msg.value,
                                _value,
                                _gasLimit,
                                _isCreation,
                                _data
                            );
                            // Emit a TransactionDeposited event so that the rollup node can derive a deposit
                            // transaction for this deposit.
                            emit TransactionDeposited(from, _to, DEPOSIT_VERSION, opaqueData);
                        }
                        /// @notice Determine if a given output is finalized.
                        ///         Reverts if the call to L2_ORACLE.getL2Output reverts.
                        ///         Returns a boolean otherwise.
                        /// @param _l2OutputIndex Index of the L2 output to check.
                        /// @return Whether or not the output is finalized.
                        function isOutputFinalized(uint256 _l2OutputIndex) external view returns (bool) {
                            return _isFinalizationPeriodElapsed(L2_ORACLE.getL2Output(_l2OutputIndex).timestamp);
                        }
                        /// @notice Determines whether the finalization period has elapsed with respect to
                        ///         the provided block timestamp.
                        /// @param _timestamp Timestamp to check.
                        /// @return Whether or not the finalization period has elapsed.
                        function _isFinalizationPeriodElapsed(uint256 _timestamp) internal view returns (bool) {
                            return block.timestamp > _timestamp + L2_ORACLE.FINALIZATION_PERIOD_SECONDS();
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    // OpenZeppelin Contracts (last updated v4.7.0) (proxy/utils/Initializable.sol)
                    pragma solidity ^0.8.2;
                    import "../../utils/Address.sol";
                    /**
                     * @dev This is a base contract to aid in writing upgradeable contracts, or any kind of contract that will be deployed
                     * behind a proxy. Since proxied contracts do not make use of a constructor, it's common to move constructor logic to an
                     * external initializer function, usually called `initialize`. It then becomes necessary to protect this initializer
                     * function so it can only be called once. The {initializer} modifier provided by this contract will have this effect.
                     *
                     * The initialization functions use a version number. Once a version number is used, it is consumed and cannot be
                     * reused. This mechanism prevents re-execution of each "step" but allows the creation of new initialization steps in
                     * case an upgrade adds a module that needs to be initialized.
                     *
                     * For example:
                     *
                     * [.hljs-theme-light.nopadding]
                     * ```
                     * contract MyToken is ERC20Upgradeable {
                     *     function initialize() initializer public {
                     *         __ERC20_init("MyToken", "MTK");
                     *     }
                     * }
                     * contract MyTokenV2 is MyToken, ERC20PermitUpgradeable {
                     *     function initializeV2() reinitializer(2) public {
                     *         __ERC20Permit_init("MyToken");
                     *     }
                     * }
                     * ```
                     *
                     * TIP: To avoid leaving the proxy in an uninitialized state, the initializer function should be called as early as
                     * possible by providing the encoded function call as the `_data` argument to {ERC1967Proxy-constructor}.
                     *
                     * CAUTION: When used with inheritance, manual care must be taken to not invoke a parent initializer twice, or to ensure
                     * that all initializers are idempotent. This is not verified automatically as constructors are by Solidity.
                     *
                     * [CAUTION]
                     * ====
                     * Avoid leaving a contract uninitialized.
                     *
                     * An uninitialized contract can be taken over by an attacker. This applies to both a proxy and its implementation
                     * contract, which may impact the proxy. To prevent the implementation contract from being used, you should invoke
                     * the {_disableInitializers} function in the constructor to automatically lock it when it is deployed:
                     *
                     * [.hljs-theme-light.nopadding]
                     * ```
                     * /// @custom:oz-upgrades-unsafe-allow constructor
                     * constructor() {
                     *     _disableInitializers();
                     * }
                     * ```
                     * ====
                     */
                    abstract contract Initializable {
                        /**
                         * @dev Indicates that the contract has been initialized.
                         * @custom:oz-retyped-from bool
                         */
                        uint8 private _initialized;
                        /**
                         * @dev Indicates that the contract is in the process of being initialized.
                         */
                        bool private _initializing;
                        /**
                         * @dev Triggered when the contract has been initialized or reinitialized.
                         */
                        event Initialized(uint8 version);
                        /**
                         * @dev A modifier that defines a protected initializer function that can be invoked at most once. In its scope,
                         * `onlyInitializing` functions can be used to initialize parent contracts. Equivalent to `reinitializer(1)`.
                         */
                        modifier initializer() {
                            bool isTopLevelCall = !_initializing;
                            require(
                                (isTopLevelCall && _initialized < 1) || (!Address.isContract(address(this)) && _initialized == 1),
                                "Initializable: contract is already initialized"
                            );
                            _initialized = 1;
                            if (isTopLevelCall) {
                                _initializing = true;
                            }
                            _;
                            if (isTopLevelCall) {
                                _initializing = false;
                                emit Initialized(1);
                            }
                        }
                        /**
                         * @dev A modifier that defines a protected reinitializer function that can be invoked at most once, and only if the
                         * contract hasn't been initialized to a greater version before. In its scope, `onlyInitializing` functions can be
                         * used to initialize parent contracts.
                         *
                         * `initializer` is equivalent to `reinitializer(1)`, so a reinitializer may be used after the original
                         * initialization step. This is essential to configure modules that are added through upgrades and that require
                         * initialization.
                         *
                         * Note that versions can jump in increments greater than 1; this implies that if multiple reinitializers coexist in
                         * a contract, executing them in the right order is up to the developer or operator.
                         */
                        modifier reinitializer(uint8 version) {
                            require(!_initializing && _initialized < version, "Initializable: contract is already initialized");
                            _initialized = version;
                            _initializing = true;
                            _;
                            _initializing = false;
                            emit Initialized(version);
                        }
                        /**
                         * @dev Modifier to protect an initialization function so that it can only be invoked by functions with the
                         * {initializer} and {reinitializer} modifiers, directly or indirectly.
                         */
                        modifier onlyInitializing() {
                            require(_initializing, "Initializable: contract is not initializing");
                            _;
                        }
                        /**
                         * @dev Locks the contract, preventing any future reinitialization. This cannot be part of an initializer call.
                         * Calling this in the constructor of a contract will prevent that contract from being initialized or reinitialized
                         * to any version. It is recommended to use this to lock implementation contracts that are designed to be called
                         * through proxies.
                         */
                        function _disableInitializers() internal virtual {
                            require(!_initializing, "Initializable: contract is initializing");
                            if (_initialized < type(uint8).max) {
                                _initialized = type(uint8).max;
                                emit Initialized(type(uint8).max);
                            }
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    pragma solidity 0.8.15;
                    /// @title SafeCall
                    /// @notice Perform low level safe calls
                    library SafeCall {
                        /// @notice Performs a low level call without copying any returndata.
                        /// @dev Passes no calldata to the call context.
                        /// @param _target   Address to call
                        /// @param _gas      Amount of gas to pass to the call
                        /// @param _value    Amount of value to pass to the call
                        function send(
                            address _target,
                            uint256 _gas,
                            uint256 _value
                        ) internal returns (bool) {
                            bool _success;
                            assembly {
                                _success := call(
                                    _gas, // gas
                                    _target, // recipient
                                    _value, // ether value
                                    0, // inloc
                                    0, // inlen
                                    0, // outloc
                                    0 // outlen
                                )
                            }
                            return _success;
                        }
                        /// @notice Perform a low level call without copying any returndata
                        /// @param _target   Address to call
                        /// @param _gas      Amount of gas to pass to the call
                        /// @param _value    Amount of value to pass to the call
                        /// @param _calldata Calldata to pass to the call
                        function call(
                            address _target,
                            uint256 _gas,
                            uint256 _value,
                            bytes memory _calldata
                        ) internal returns (bool) {
                            bool _success;
                            assembly {
                                _success := call(
                                    _gas, // gas
                                    _target, // recipient
                                    _value, // ether value
                                    add(_calldata, 32), // inloc
                                    mload(_calldata), // inlen
                                    0, // outloc
                                    0 // outlen
                                )
                            }
                            return _success;
                        }
                        /// @notice Helper function to determine if there is sufficient gas remaining within the context
                        ///         to guarantee that the minimum gas requirement for a call will be met as well as
                        ///         optionally reserving a specified amount of gas for after the call has concluded.
                        /// @param _minGas      The minimum amount of gas that may be passed to the target context.
                        /// @param _reservedGas Optional amount of gas to reserve for the caller after the execution
                        ///                     of the target context.
                        /// @return `true` if there is enough gas remaining to safely supply `_minGas` to the target
                        ///         context as well as reserve `_reservedGas` for the caller after the execution of
                        ///         the target context.
                        /// @dev !!!!! FOOTGUN ALERT !!!!!
                        ///      1.) The 40_000 base buffer is to account for the worst case of the dynamic cost of the
                        ///          `CALL` opcode's `address_access_cost`, `positive_value_cost`, and
                        ///          `value_to_empty_account_cost` factors with an added buffer of 5,700 gas. It is
                        ///          still possible to self-rekt by initiating a withdrawal with a minimum gas limit
                        ///          that does not account for the `memory_expansion_cost` & `code_execution_cost`
                        ///          factors of the dynamic cost of the `CALL` opcode.
                        ///      2.) This function should *directly* precede the external call if possible. There is an
                        ///          added buffer to account for gas consumed between this check and the call, but it
                        ///          is only 5,700 gas.
                        ///      3.) Because EIP-150 ensures that a maximum of 63/64ths of the remaining gas in the call
                        ///          frame may be passed to a subcontext, we need to ensure that the gas will not be
                        ///          truncated.
                        ///      4.) Use wisely. This function is not a silver bullet.
                        function hasMinGas(uint256 _minGas, uint256 _reservedGas) internal view returns (bool) {
                            bool _hasMinGas;
                            assembly {
                                // Equation: gas × 63 ≥ minGas × 64 + 63(40_000 + reservedGas)
                                _hasMinGas := iszero(
                                    lt(mul(gas(), 63), add(mul(_minGas, 64), mul(add(40000, _reservedGas), 63)))
                                )
                            }
                            return _hasMinGas;
                        }
                        /// @notice Perform a low level call without copying any returndata. This function
                        ///         will revert if the call cannot be performed with the specified minimum
                        ///         gas.
                        /// @param _target   Address to call
                        /// @param _minGas   The minimum amount of gas that may be passed to the call
                        /// @param _value    Amount of value to pass to the call
                        /// @param _calldata Calldata to pass to the call
                        function callWithMinGas(
                            address _target,
                            uint256 _minGas,
                            uint256 _value,
                            bytes memory _calldata
                        ) internal returns (bool) {
                            bool _success;
                            bool _hasMinGas = hasMinGas(_minGas, 0);
                            assembly {
                                // Assertion: gasleft() >= (_minGas * 64) / 63 + 40_000
                                if iszero(_hasMinGas) {
                                    // Store the "Error(string)" selector in scratch space.
                                    mstore(0, 0x08c379a0)
                                    // Store the pointer to the string length in scratch space.
                                    mstore(32, 32)
                                    // Store the string.
                                    //
                                    // SAFETY:
                                    // - We pad the beginning of the string with two zero bytes as well as the
                                    // length (24) to ensure that we override the free memory pointer at offset
                                    // 0x40. This is necessary because the free memory pointer is likely to
                                    // be greater than 1 byte when this function is called, but it is incredibly
                                    // unlikely that it will be greater than 3 bytes. As for the data within
                                    // 0x60, it is ensured that it is 0 due to 0x60 being the zero offset.
                                    // - It's fine to clobber the free memory pointer, we're reverting.
                                    mstore(88, 0x0000185361666543616c6c3a204e6f7420656e6f75676820676173)
                                    // Revert with 'Error("SafeCall: Not enough gas")'
                                    revert(28, 100)
                                }
                                // The call will be supplied at least ((_minGas * 64) / 63) gas due to the
                                // above assertion. This ensures that, in all circumstances (except for when the
                                // `_minGas` does not account for the `memory_expansion_cost` and `code_execution_cost`
                                // factors of the dynamic cost of the `CALL` opcode), the call will receive at least
                                // the minimum amount of gas specified.
                                _success := call(
                                    gas(), // gas
                                    _target, // recipient
                                    _value, // ether value
                                    add(_calldata, 32), // inloc
                                    mload(_calldata), // inlen
                                    0x00, // outloc
                                    0x00 // outlen
                                )
                            }
                            return _success;
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    pragma solidity 0.8.15;
                    import { Initializable } from "@openzeppelin/contracts/proxy/utils/Initializable.sol";
                    import { Semver } from "../universal/Semver.sol";
                    import { Types } from "../libraries/Types.sol";
                    /// @custom:proxied
                    /// @title L2OutputOracle
                    /// @notice The L2OutputOracle contains an array of L2 state outputs, where each output is a
                    ///         commitment to the state of the L2 chain. Other contracts like the OptimismPortal use
                    ///         these outputs to verify information about the state of L2.
                    contract L2OutputOracle is Initializable, Semver {
                        /// @notice The interval in L2 blocks at which checkpoints must be submitted.
                        ///         Although this is immutable, it can safely be modified by upgrading the
                        ///         implementation contract.
                        uint256 public immutable SUBMISSION_INTERVAL;
                        /// @notice The time between L2 blocks in seconds. Once set, this value MUST NOT be modified.
                        uint256 public immutable L2_BLOCK_TIME;
                        /// @notice The address of the challenger. Can be updated via upgrade.
                        address public immutable CHALLENGER;
                        /// @notice The address of the proposer. Can be updated via upgrade.
                        address public immutable PROPOSER;
                        /// @notice The minimum time (in seconds) that must elapse before a withdrawal can be finalized.
                        uint256 public immutable FINALIZATION_PERIOD_SECONDS;
                        /// @notice The number of the first L2 block recorded in this contract.
                        uint256 public startingBlockNumber;
                        /// @notice The timestamp of the first L2 block recorded in this contract.
                        uint256 public startingTimestamp;
                        /// @notice An array of L2 output proposals.
                        Types.OutputProposal[] internal l2Outputs;
                        /// @notice Emitted when an output is proposed.
                        /// @param outputRoot    The output root.
                        /// @param l2OutputIndex The index of the output in the l2Outputs array.
                        /// @param l2BlockNumber The L2 block number of the output root.
                        /// @param l1Timestamp   The L1 timestamp when proposed.
                        event OutputProposed(
                            bytes32 indexed outputRoot,
                            uint256 indexed l2OutputIndex,
                            uint256 indexed l2BlockNumber,
                            uint256 l1Timestamp
                        );
                        /// @notice Emitted when outputs are deleted.
                        /// @param prevNextOutputIndex Next L2 output index before the deletion.
                        /// @param newNextOutputIndex  Next L2 output index after the deletion.
                        event OutputsDeleted(uint256 indexed prevNextOutputIndex, uint256 indexed newNextOutputIndex);
                        /// @custom:semver 1.3.1
                        /// @notice Constructs the L2OutputOracle contract.
                        /// @param _submissionInterval  Interval in blocks at which checkpoints must be submitted.
                        /// @param _l2BlockTime         The time per L2 block, in seconds.
                        /// @param _startingBlockNumber The number of the first L2 block.
                        /// @param _startingTimestamp   The timestamp of the first L2 block.
                        /// @param _proposer            The address of the proposer.
                        /// @param _challenger          The address of the challenger.
                        constructor(
                            uint256 _submissionInterval,
                            uint256 _l2BlockTime,
                            uint256 _startingBlockNumber,
                            uint256 _startingTimestamp,
                            address _proposer,
                            address _challenger,
                            uint256 _finalizationPeriodSeconds
                        ) Semver(1, 3, 1) {
                            require(_l2BlockTime > 0, "L2OutputOracle: L2 block time must be greater than 0");
                            require(
                                _submissionInterval > 0,
                                "L2OutputOracle: submission interval must be greater than 0"
                            );
                            SUBMISSION_INTERVAL = _submissionInterval;
                            L2_BLOCK_TIME = _l2BlockTime;
                            PROPOSER = _proposer;
                            CHALLENGER = _challenger;
                            FINALIZATION_PERIOD_SECONDS = _finalizationPeriodSeconds;
                            initialize(_startingBlockNumber, _startingTimestamp);
                        }
                        /// @notice Initializer.
                        /// @param _startingBlockNumber Block number for the first recoded L2 block.
                        /// @param _startingTimestamp   Timestamp for the first recoded L2 block.
                        function initialize(uint256 _startingBlockNumber, uint256 _startingTimestamp)
                            public
                            initializer
                        {
                            require(
                                _startingTimestamp <= block.timestamp,
                                "L2OutputOracle: starting L2 timestamp must be less than current time"
                            );
                            startingTimestamp = _startingTimestamp;
                            startingBlockNumber = _startingBlockNumber;
                        }
                        /// @notice Deletes all output proposals after and including the proposal that corresponds to
                        ///         the given output index. Only the challenger address can delete outputs.
                        /// @param _l2OutputIndex Index of the first L2 output to be deleted.
                        ///                       All outputs after this output will also be deleted.
                        // solhint-disable-next-line ordering
                        function deleteL2Outputs(uint256 _l2OutputIndex) external {
                            require(
                                msg.sender == CHALLENGER,
                                "L2OutputOracle: only the challenger address can delete outputs"
                            );
                            // Make sure we're not *increasing* the length of the array.
                            require(
                                _l2OutputIndex < l2Outputs.length,
                                "L2OutputOracle: cannot delete outputs after the latest output index"
                            );
                            // Do not allow deleting any outputs that have already been finalized.
                            require(
                                block.timestamp - l2Outputs[_l2OutputIndex].timestamp < FINALIZATION_PERIOD_SECONDS,
                                "L2OutputOracle: cannot delete outputs that have already been finalized"
                            );
                            uint256 prevNextL2OutputIndex = nextOutputIndex();
                            // Use assembly to delete the array elements because Solidity doesn't allow it.
                            assembly {
                                sstore(l2Outputs.slot, _l2OutputIndex)
                            }
                            emit OutputsDeleted(prevNextL2OutputIndex, _l2OutputIndex);
                        }
                        /// @notice Accepts an outputRoot and the timestamp of the corresponding L2 block.
                        ///         The timestamp must be equal to the current value returned by `nextTimestamp()` in
                        ///         order to be accepted. This function may only be called by the Proposer.
                        /// @param _outputRoot    The L2 output of the checkpoint block.
                        /// @param _l2BlockNumber The L2 block number that resulted in _outputRoot.
                        /// @param _l1BlockHash   A block hash which must be included in the current chain.
                        /// @param _l1BlockNumber The block number with the specified block hash.
                        function proposeL2Output(
                            bytes32 _outputRoot,
                            uint256 _l2BlockNumber,
                            bytes32 _l1BlockHash,
                            uint256 _l1BlockNumber
                        ) external payable {
                            require(
                                msg.sender == PROPOSER,
                                "L2OutputOracle: only the proposer address can propose new outputs"
                            );
                            require(
                                _l2BlockNumber == nextBlockNumber(),
                                "L2OutputOracle: block number must be equal to next expected block number"
                            );
                            require(
                                computeL2Timestamp(_l2BlockNumber) < block.timestamp,
                                "L2OutputOracle: cannot propose L2 output in the future"
                            );
                            require(
                                _outputRoot != bytes32(0),
                                "L2OutputOracle: L2 output proposal cannot be the zero hash"
                            );
                            if (_l1BlockHash != bytes32(0)) {
                                // This check allows the proposer to propose an output based on a given L1 block,
                                // without fear that it will be reorged out.
                                // It will also revert if the blockheight provided is more than 256 blocks behind the
                                // chain tip (as the hash will return as zero). This does open the door to a griefing
                                // attack in which the proposer's submission is censored until the block is no longer
                                // retrievable, if the proposer is experiencing this attack it can simply leave out the
                                // blockhash value, and delay submission until it is confident that the L1 block is
                                // finalized.
                                require(
                                    blockhash(_l1BlockNumber) == _l1BlockHash,
                                    "L2OutputOracle: block hash does not match the hash at the expected height"
                                );
                            }
                            emit OutputProposed(_outputRoot, nextOutputIndex(), _l2BlockNumber, block.timestamp);
                            l2Outputs.push(
                                Types.OutputProposal({
                                    outputRoot: _outputRoot,
                                    timestamp: uint128(block.timestamp),
                                    l2BlockNumber: uint128(_l2BlockNumber)
                                })
                            );
                        }
                        /// @notice Returns an output by index. Needed to return a struct instead of a tuple.
                        /// @param _l2OutputIndex Index of the output to return.
                        /// @return The output at the given index.
                        function getL2Output(uint256 _l2OutputIndex)
                            external
                            view
                            returns (Types.OutputProposal memory)
                        {
                            return l2Outputs[_l2OutputIndex];
                        }
                        /// @notice Returns the index of the L2 output that checkpoints a given L2 block number.
                        ///         Uses a binary search to find the first output greater than or equal to the given
                        ///         block.
                        /// @param _l2BlockNumber L2 block number to find a checkpoint for.
                        /// @return Index of the first checkpoint that commits to the given L2 block number.
                        function getL2OutputIndexAfter(uint256 _l2BlockNumber) public view returns (uint256) {
                            // Make sure an output for this block number has actually been proposed.
                            require(
                                _l2BlockNumber <= latestBlockNumber(),
                                "L2OutputOracle: cannot get output for a block that has not been proposed"
                            );
                            // Make sure there's at least one output proposed.
                            require(
                                l2Outputs.length > 0,
                                "L2OutputOracle: cannot get output as no outputs have been proposed yet"
                            );
                            // Find the output via binary search, guaranteed to exist.
                            uint256 lo = 0;
                            uint256 hi = l2Outputs.length;
                            while (lo < hi) {
                                uint256 mid = (lo + hi) / 2;
                                if (l2Outputs[mid].l2BlockNumber < _l2BlockNumber) {
                                    lo = mid + 1;
                                } else {
                                    hi = mid;
                                }
                            }
                            return lo;
                        }
                        /// @notice Returns the L2 output proposal that checkpoints a given L2 block number.
                        ///         Uses a binary search to find the first output greater than or equal to the given
                        ///         block.
                        /// @param _l2BlockNumber L2 block number to find a checkpoint for.
                        /// @return First checkpoint that commits to the given L2 block number.
                        function getL2OutputAfter(uint256 _l2BlockNumber)
                            external
                            view
                            returns (Types.OutputProposal memory)
                        {
                            return l2Outputs[getL2OutputIndexAfter(_l2BlockNumber)];
                        }
                        /// @notice Returns the number of outputs that have been proposed.
                        ///         Will revert if no outputs have been proposed yet.
                        /// @return The number of outputs that have been proposed.
                        function latestOutputIndex() external view returns (uint256) {
                            return l2Outputs.length - 1;
                        }
                        /// @notice Returns the index of the next output to be proposed.
                        /// @return The index of the next output to be proposed.
                        function nextOutputIndex() public view returns (uint256) {
                            return l2Outputs.length;
                        }
                        /// @notice Returns the block number of the latest submitted L2 output proposal.
                        ///         If no proposals been submitted yet then this function will return the starting
                        ///         block number.
                        /// @return Latest submitted L2 block number.
                        function latestBlockNumber() public view returns (uint256) {
                            return
                                l2Outputs.length == 0
                                    ? startingBlockNumber
                                    : l2Outputs[l2Outputs.length - 1].l2BlockNumber;
                        }
                        /// @notice Computes the block number of the next L2 block that needs to be checkpointed.
                        /// @return Next L2 block number.
                        function nextBlockNumber() public view returns (uint256) {
                            return latestBlockNumber() + SUBMISSION_INTERVAL;
                        }
                        /// @notice Returns the L2 timestamp corresponding to a given L2 block number.
                        /// @param _l2BlockNumber The L2 block number of the target block.
                        /// @return L2 timestamp of the given block.
                        function computeL2Timestamp(uint256 _l2BlockNumber) public view returns (uint256) {
                            return startingTimestamp + ((_l2BlockNumber - startingBlockNumber) * L2_BLOCK_TIME);
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    pragma solidity 0.8.15;
                    import {
                        OwnableUpgradeable
                    } from "@openzeppelin/contracts-upgradeable/access/OwnableUpgradeable.sol";
                    import { Semver } from "../universal/Semver.sol";
                    import { ResourceMetering } from "./ResourceMetering.sol";
                    /// @title SystemConfig
                    /// @notice The SystemConfig contract is used to manage configuration of an Optimism network.
                    ///         All configuration is stored on L1 and picked up by L2 as part of the derviation of
                    ///         the L2 chain.
                    contract SystemConfig is OwnableUpgradeable, Semver {
                        /// @notice Enum representing different types of updates.
                        /// @custom:value BATCHER              Represents an update to the batcher hash.
                        /// @custom:value GAS_CONFIG           Represents an update to txn fee config on L2.
                        /// @custom:value GAS_LIMIT            Represents an update to gas limit on L2.
                        /// @custom:value UNSAFE_BLOCK_SIGNER  Represents an update to the signer key for unsafe
                        ///                                    block distrubution.
                        enum UpdateType {
                            BATCHER,
                            GAS_CONFIG,
                            GAS_LIMIT,
                            UNSAFE_BLOCK_SIGNER
                        }
                        /// @notice Version identifier, used for upgrades.
                        uint256 public constant VERSION = 0;
                        /// @notice Storage slot that the unsafe block signer is stored at.
                        ///         Storing it at this deterministic storage slot allows for decoupling the storage
                        ///         layout from the way that `solc` lays out storage. The `op-node` uses a storage
                        ///         proof to fetch this value.
                        bytes32 public constant UNSAFE_BLOCK_SIGNER_SLOT = keccak256("systemconfig.unsafeblocksigner");
                        /// @notice Fixed L2 gas overhead. Used as part of the L2 fee calculation.
                        uint256 public overhead;
                        /// @notice Dynamic L2 gas overhead. Used as part of the L2 fee calculation.
                        uint256 public scalar;
                        /// @notice Identifier for the batcher.
                        ///         For version 1 of this configuration, this is represented as an address left-padded
                        ///         with zeros to 32 bytes.
                        bytes32 public batcherHash;
                        /// @notice L2 block gas limit.
                        uint64 public gasLimit;
                        /// @notice The configuration for the deposit fee market.
                        ///         Used by the OptimismPortal to meter the cost of buying L2 gas on L1.
                        ///         Set as internal with a getter so that the struct is returned instead of a tuple.
                        ResourceMetering.ResourceConfig internal _resourceConfig;
                        /// @notice Emitted when configuration is updated.
                        /// @param version    SystemConfig version.
                        /// @param updateType Type of update.
                        /// @param data       Encoded update data.
                        event ConfigUpdate(uint256 indexed version, UpdateType indexed updateType, bytes data);
                        /// @custom:semver 1.3.1
                        /// @notice Constructs the SystemConfig contract.
                        /// @param _owner             Initial owner of the contract.
                        /// @param _overhead          Initial overhead value.
                        /// @param _scalar            Initial scalar value.
                        /// @param _batcherHash       Initial batcher hash.
                        /// @param _gasLimit          Initial gas limit.
                        /// @param _unsafeBlockSigner Initial unsafe block signer address.
                        /// @param _config            Initial resource config.
                        constructor(
                            address _owner,
                            uint256 _overhead,
                            uint256 _scalar,
                            bytes32 _batcherHash,
                            uint64 _gasLimit,
                            address _unsafeBlockSigner,
                            ResourceMetering.ResourceConfig memory _config
                        ) Semver(1, 3, 1) {
                            initialize({
                                _owner: _owner,
                                _overhead: _overhead,
                                _scalar: _scalar,
                                _batcherHash: _batcherHash,
                                _gasLimit: _gasLimit,
                                _unsafeBlockSigner: _unsafeBlockSigner,
                                _config: _config
                            });
                        }
                        /// @notice Initializer.
                        ///         The resource config must be set before the require check.
                        /// @param _owner             Initial owner of the contract.
                        /// @param _overhead          Initial overhead value.
                        /// @param _scalar            Initial scalar value.
                        /// @param _batcherHash       Initial batcher hash.
                        /// @param _gasLimit          Initial gas limit.
                        /// @param _unsafeBlockSigner Initial unsafe block signer address.
                        /// @param _config            Initial ResourceConfig.
                        function initialize(
                            address _owner,
                            uint256 _overhead,
                            uint256 _scalar,
                            bytes32 _batcherHash,
                            uint64 _gasLimit,
                            address _unsafeBlockSigner,
                            ResourceMetering.ResourceConfig memory _config
                        ) public initializer {
                            __Ownable_init();
                            transferOwnership(_owner);
                            overhead = _overhead;
                            scalar = _scalar;
                            batcherHash = _batcherHash;
                            gasLimit = _gasLimit;
                            _setUnsafeBlockSigner(_unsafeBlockSigner);
                            _setResourceConfig(_config);
                            require(_gasLimit >= minimumGasLimit(), "SystemConfig: gas limit too low");
                        }
                        /// @notice Returns the minimum L2 gas limit that can be safely set for the system to
                        ///         operate. The L2 gas limit must be larger than or equal to the amount of
                        ///         gas that is allocated for deposits per block plus the amount of gas that
                        ///         is allocated for the system transaction.
                        ///         This function is used to determine if changes to parameters are safe.
                        /// @return uint64 Minimum gas limit.
                        function minimumGasLimit() public view returns (uint64) {
                            return uint64(_resourceConfig.maxResourceLimit) + uint64(_resourceConfig.systemTxMaxGas);
                        }
                        /// @notice High level getter for the unsafe block signer address.
                        ///         Unsafe blocks can be propagated across the p2p network if they are signed by the
                        ///         key corresponding to this address.
                        /// @return Address of the unsafe block signer.
                        // solhint-disable-next-line ordering
                        function unsafeBlockSigner() external view returns (address) {
                            address addr;
                            bytes32 slot = UNSAFE_BLOCK_SIGNER_SLOT;
                            assembly {
                                addr := sload(slot)
                            }
                            return addr;
                        }
                        /// @notice Updates the unsafe block signer address.
                        /// @param _unsafeBlockSigner New unsafe block signer address.
                        function setUnsafeBlockSigner(address _unsafeBlockSigner) external onlyOwner {
                            _setUnsafeBlockSigner(_unsafeBlockSigner);
                            bytes memory data = abi.encode(_unsafeBlockSigner);
                            emit ConfigUpdate(VERSION, UpdateType.UNSAFE_BLOCK_SIGNER, data);
                        }
                        /// @notice Updates the batcher hash.
                        /// @param _batcherHash New batcher hash.
                        function setBatcherHash(bytes32 _batcherHash) external onlyOwner {
                            batcherHash = _batcherHash;
                            bytes memory data = abi.encode(_batcherHash);
                            emit ConfigUpdate(VERSION, UpdateType.BATCHER, data);
                        }
                        /// @notice Updates gas config.
                        /// @param _overhead New overhead value.
                        /// @param _scalar   New scalar value.
                        function setGasConfig(uint256 _overhead, uint256 _scalar) external onlyOwner {
                            overhead = _overhead;
                            scalar = _scalar;
                            bytes memory data = abi.encode(_overhead, _scalar);
                            emit ConfigUpdate(VERSION, UpdateType.GAS_CONFIG, data);
                        }
                        /// @notice Updates the L2 gas limit.
                        /// @param _gasLimit New gas limit.
                        function setGasLimit(uint64 _gasLimit) external onlyOwner {
                            require(_gasLimit >= minimumGasLimit(), "SystemConfig: gas limit too low");
                            gasLimit = _gasLimit;
                            bytes memory data = abi.encode(_gasLimit);
                            emit ConfigUpdate(VERSION, UpdateType.GAS_LIMIT, data);
                        }
                        /// @notice Low level setter for the unsafe block signer address.
                        ///         This function exists to deduplicate code around storing the unsafeBlockSigner
                        ///         address in storage.
                        /// @param _unsafeBlockSigner New unsafeBlockSigner value.
                        function _setUnsafeBlockSigner(address _unsafeBlockSigner) internal {
                            bytes32 slot = UNSAFE_BLOCK_SIGNER_SLOT;
                            assembly {
                                sstore(slot, _unsafeBlockSigner)
                            }
                        }
                        /// @notice A getter for the resource config.
                        ///         Ensures that the struct is returned instead of a tuple.
                        /// @return ResourceConfig
                        function resourceConfig() external view returns (ResourceMetering.ResourceConfig memory) {
                            return _resourceConfig;
                        }
                        /// @notice An external setter for the resource config.
                        ///         In the future, this method may emit an event that the `op-node` picks up
                        ///         for when the resource config is changed.
                        /// @param _config The new resource config values.
                        function setResourceConfig(ResourceMetering.ResourceConfig memory _config) external onlyOwner {
                            _setResourceConfig(_config);
                        }
                        /// @notice An internal setter for the resource config.
                        ///         Ensures that the config is sane before storing it by checking for invariants.
                        /// @param _config The new resource config.
                        function _setResourceConfig(ResourceMetering.ResourceConfig memory _config) internal {
                            // Min base fee must be less than or equal to max base fee.
                            require(
                                _config.minimumBaseFee <= _config.maximumBaseFee,
                                "SystemConfig: min base fee must be less than max base"
                            );
                            // Base fee change denominator must be greater than 1.
                            require(
                                _config.baseFeeMaxChangeDenominator > 1,
                                "SystemConfig: denominator must be larger than 1"
                            );
                            // Max resource limit plus system tx gas must be less than or equal to the L2 gas limit.
                            // The gas limit must be increased before these values can be increased.
                            require(
                                _config.maxResourceLimit + _config.systemTxMaxGas <= gasLimit,
                                "SystemConfig: gas limit too low"
                            );
                            // Elasticity multiplier must be greater than 0.
                            require(
                                _config.elasticityMultiplier > 0,
                                "SystemConfig: elasticity multiplier cannot be 0"
                            );
                            // No precision loss when computing target resource limit.
                            require(
                                ((_config.maxResourceLimit / _config.elasticityMultiplier) *
                                    _config.elasticityMultiplier) == _config.maxResourceLimit,
                                "SystemConfig: precision loss with target resource limit"
                            );
                            _resourceConfig = _config;
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    pragma solidity ^0.8.0;
                    import { ResourceMetering } from "../L1/ResourceMetering.sol";
                    /// @title Constants
                    /// @notice Constants is a library for storing constants. Simple! Don't put everything in here, just
                    ///         the stuff used in multiple contracts. Constants that only apply to a single contract
                    ///         should be defined in that contract instead.
                    library Constants {
                        /// @notice Special address to be used as the tx origin for gas estimation calls in the
                        ///         OptimismPortal and CrossDomainMessenger calls. You only need to use this address if
                        ///         the minimum gas limit specified by the user is not actually enough to execute the
                        ///         given message and you're attempting to estimate the actual necessary gas limit. We
                        ///         use address(1) because it's the ecrecover precompile and therefore guaranteed to
                        ///         never have any code on any EVM chain.
                        address internal constant ESTIMATION_ADDRESS = address(1);
                        /// @notice Value used for the L2 sender storage slot in both the OptimismPortal and the
                        ///         CrossDomainMessenger contracts before an actual sender is set. This value is
                        ///         non-zero to reduce the gas cost of message passing transactions.
                        address internal constant DEFAULT_L2_SENDER = 0x000000000000000000000000000000000000dEaD;
                        /// @notice Returns the default values for the ResourceConfig. These are the recommended values
                        ///         for a production network.
                        function DEFAULT_RESOURCE_CONFIG()
                            internal
                            pure
                            returns (ResourceMetering.ResourceConfig memory)
                        {
                            ResourceMetering.ResourceConfig memory config = ResourceMetering.ResourceConfig({
                                maxResourceLimit: 20_000_000,
                                elasticityMultiplier: 10,
                                baseFeeMaxChangeDenominator: 8,
                                minimumBaseFee: 1 gwei,
                                systemTxMaxGas: 1_000_000,
                                maximumBaseFee: type(uint128).max
                            });
                            return config;
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    pragma solidity ^0.8.0;
                    /// @title Types
                    /// @notice Contains various types used throughout the Optimism contract system.
                    library Types {
                        /// @notice OutputProposal represents a commitment to the L2 state. The timestamp is the L1
                        ///         timestamp that the output root is posted. This timestamp is used to verify that the
                        ///         finalization period has passed since the output root was submitted.
                        /// @custom:field outputRoot    Hash of the L2 output.
                        /// @custom:field timestamp     Timestamp of the L1 block that the output root was submitted in.
                        /// @custom:field l2BlockNumber L2 block number that the output corresponds to.
                        struct OutputProposal {
                            bytes32 outputRoot;
                            uint128 timestamp;
                            uint128 l2BlockNumber;
                        }
                        /// @notice Struct representing the elements that are hashed together to generate an output root
                        ///         which itself represents a snapshot of the L2 state.
                        /// @custom:field version                  Version of the output root.
                        /// @custom:field stateRoot                Root of the state trie at the block of this output.
                        /// @custom:field messagePasserStorageRoot Root of the message passer storage trie.
                        /// @custom:field latestBlockhash          Hash of the block this output was generated from.
                        struct OutputRootProof {
                            bytes32 version;
                            bytes32 stateRoot;
                            bytes32 messagePasserStorageRoot;
                            bytes32 latestBlockhash;
                        }
                        /// @notice Struct representing a deposit transaction (L1 => L2 transaction) created by an end
                        ///         user (as opposed to a system deposit transaction generated by the system).
                        /// @custom:field from        Address of the sender of the transaction.
                        /// @custom:field to          Address of the recipient of the transaction.
                        /// @custom:field isCreation  True if the transaction is a contract creation.
                        /// @custom:field value       Value to send to the recipient.
                        /// @custom:field mint        Amount of ETH to mint.
                        /// @custom:field gasLimit    Gas limit of the transaction.
                        /// @custom:field data        Data of the transaction.
                        /// @custom:field l1BlockHash Hash of the block the transaction was submitted in.
                        /// @custom:field logIndex    Index of the log in the block the transaction was submitted in.
                        struct UserDepositTransaction {
                            address from;
                            address to;
                            bool isCreation;
                            uint256 value;
                            uint256 mint;
                            uint64 gasLimit;
                            bytes data;
                            bytes32 l1BlockHash;
                            uint256 logIndex;
                        }
                        /// @notice Struct representing a withdrawal transaction.
                        /// @custom:field nonce    Nonce of the withdrawal transaction
                        /// @custom:field sender   Address of the sender of the transaction.
                        /// @custom:field target   Address of the recipient of the transaction.
                        /// @custom:field value    Value to send to the recipient.
                        /// @custom:field gasLimit Gas limit of the transaction.
                        /// @custom:field data     Data of the transaction.
                        struct WithdrawalTransaction {
                            uint256 nonce;
                            address sender;
                            address target;
                            uint256 value;
                            uint256 gasLimit;
                            bytes data;
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    pragma solidity ^0.8.0;
                    import { Types } from "./Types.sol";
                    import { Encoding } from "./Encoding.sol";
                    /// @title Hashing
                    /// @notice Hashing handles Optimism's various different hashing schemes.
                    library Hashing {
                        /// @notice Computes the hash of the RLP encoded L2 transaction that would be generated when a
                        ///         given deposit is sent to the L2 system. Useful for searching for a deposit in the L2
                        ///         system.
                        /// @param _tx User deposit transaction to hash.
                        /// @return Hash of the RLP encoded L2 deposit transaction.
                        function hashDepositTransaction(Types.UserDepositTransaction memory _tx)
                            internal
                            pure
                            returns (bytes32)
                        {
                            return keccak256(Encoding.encodeDepositTransaction(_tx));
                        }
                        /// @notice Computes the deposit transaction's "source hash", a value that guarantees the hash
                        ///         of the L2 transaction that corresponds to a deposit is unique and is
                        ///         deterministically generated from L1 transaction data.
                        /// @param _l1BlockHash Hash of the L1 block where the deposit was included.
                        /// @param _logIndex    The index of the log that created the deposit transaction.
                        /// @return Hash of the deposit transaction's "source hash".
                        function hashDepositSource(bytes32 _l1BlockHash, uint256 _logIndex)
                            internal
                            pure
                            returns (bytes32)
                        {
                            bytes32 depositId = keccak256(abi.encode(_l1BlockHash, _logIndex));
                            return keccak256(abi.encode(bytes32(0), depositId));
                        }
                        /// @notice Hashes the cross domain message based on the version that is encoded into the
                        ///         message nonce.
                        /// @param _nonce    Message nonce with version encoded into the first two bytes.
                        /// @param _sender   Address of the sender of the message.
                        /// @param _target   Address of the target of the message.
                        /// @param _value    ETH value to send to the target.
                        /// @param _gasLimit Gas limit to use for the message.
                        /// @param _data     Data to send with the message.
                        /// @return Hashed cross domain message.
                        function hashCrossDomainMessage(
                            uint256 _nonce,
                            address _sender,
                            address _target,
                            uint256 _value,
                            uint256 _gasLimit,
                            bytes memory _data
                        ) internal pure returns (bytes32) {
                            (, uint16 version) = Encoding.decodeVersionedNonce(_nonce);
                            if (version == 0) {
                                return hashCrossDomainMessageV0(_target, _sender, _data, _nonce);
                            } else if (version == 1) {
                                return hashCrossDomainMessageV1(_nonce, _sender, _target, _value, _gasLimit, _data);
                            } else {
                                revert("Hashing: unknown cross domain message version");
                            }
                        }
                        /// @notice Hashes a cross domain message based on the V0 (legacy) encoding.
                        /// @param _target Address of the target of the message.
                        /// @param _sender Address of the sender of the message.
                        /// @param _data   Data to send with the message.
                        /// @param _nonce  Message nonce.
                        /// @return Hashed cross domain message.
                        function hashCrossDomainMessageV0(
                            address _target,
                            address _sender,
                            bytes memory _data,
                            uint256 _nonce
                        ) internal pure returns (bytes32) {
                            return keccak256(Encoding.encodeCrossDomainMessageV0(_target, _sender, _data, _nonce));
                        }
                        /// @notice Hashes a cross domain message based on the V1 (current) encoding.
                        /// @param _nonce    Message nonce.
                        /// @param _sender   Address of the sender of the message.
                        /// @param _target   Address of the target of the message.
                        /// @param _value    ETH value to send to the target.
                        /// @param _gasLimit Gas limit to use for the message.
                        /// @param _data     Data to send with the message.
                        /// @return Hashed cross domain message.
                        function hashCrossDomainMessageV1(
                            uint256 _nonce,
                            address _sender,
                            address _target,
                            uint256 _value,
                            uint256 _gasLimit,
                            bytes memory _data
                        ) internal pure returns (bytes32) {
                            return
                                keccak256(
                                    Encoding.encodeCrossDomainMessageV1(
                                        _nonce,
                                        _sender,
                                        _target,
                                        _value,
                                        _gasLimit,
                                        _data
                                    )
                                );
                        }
                        /// @notice Derives the withdrawal hash according to the encoding in the L2 Withdrawer contract
                        /// @param _tx Withdrawal transaction to hash.
                        /// @return Hashed withdrawal transaction.
                        function hashWithdrawal(Types.WithdrawalTransaction memory _tx)
                            internal
                            pure
                            returns (bytes32)
                        {
                            return
                                keccak256(
                                    abi.encode(_tx.nonce, _tx.sender, _tx.target, _tx.value, _tx.gasLimit, _tx.data)
                                );
                        }
                        /// @notice Hashes the various elements of an output root proof into an output root hash which
                        ///         can be used to check if the proof is valid.
                        /// @param _outputRootProof Output root proof which should hash to an output root.
                        /// @return Hashed output root proof.
                        function hashOutputRootProof(Types.OutputRootProof memory _outputRootProof)
                            internal
                            pure
                            returns (bytes32)
                        {
                            return
                                keccak256(
                                    abi.encode(
                                        _outputRootProof.version,
                                        _outputRootProof.stateRoot,
                                        _outputRootProof.messagePasserStorageRoot,
                                        _outputRootProof.latestBlockhash
                                    )
                                );
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    pragma solidity ^0.8.0;
                    /* Library Imports */
                    import { MerkleTrie } from "./MerkleTrie.sol";
                    /**
                     * @title SecureMerkleTrie
                     * @notice SecureMerkleTrie is a thin wrapper around the MerkleTrie library that hashes the input
                     *         keys. Ethereum's state trie hashes input keys before storing them.
                     */
                    library SecureMerkleTrie {
                        /**
                         * @notice Verifies a proof that a given key/value pair is present in the Merkle trie.
                         *
                         * @param _key   Key of the node to search for, as a hex string.
                         * @param _value Value of the node to search for, as a hex string.
                         * @param _proof Merkle trie inclusion proof for the desired node. Unlike traditional Merkle
                         *               trees, this proof is executed top-down and consists of a list of RLP-encoded
                         *               nodes that make a path down to the target node.
                         * @param _root  Known root of the Merkle trie. Used to verify that the included proof is
                         *               correctly constructed.
                         *
                         * @return Whether or not the proof is valid.
                         */
                        function verifyInclusionProof(
                            bytes memory _key,
                            bytes memory _value,
                            bytes[] memory _proof,
                            bytes32 _root
                        ) internal pure returns (bool) {
                            bytes memory key = _getSecureKey(_key);
                            return MerkleTrie.verifyInclusionProof(key, _value, _proof, _root);
                        }
                        /**
                         * @notice Retrieves the value associated with a given key.
                         *
                         * @param _key   Key to search for, as hex bytes.
                         * @param _proof Merkle trie inclusion proof for the key.
                         * @param _root  Known root of the Merkle trie.
                         *
                         * @return Value of the key if it exists.
                         */
                        function get(
                            bytes memory _key,
                            bytes[] memory _proof,
                            bytes32 _root
                        ) internal pure returns (bytes memory) {
                            bytes memory key = _getSecureKey(_key);
                            return MerkleTrie.get(key, _proof, _root);
                        }
                        /**
                         * @notice Computes the hashed version of the input key.
                         *
                         * @param _key Key to hash.
                         *
                         * @return Hashed version of the key.
                         */
                        function _getSecureKey(bytes memory _key) private pure returns (bytes memory) {
                            return abi.encodePacked(keccak256(_key));
                        }
                    }
                    // SPDX-License-Identifier: Apache-2.0
                    /*
                     * Copyright 2019-2021, Offchain Labs, Inc.
                     *
                     * Licensed under the Apache License, Version 2.0 (the "License");
                     * you may not use this file except in compliance with the License.
                     * You may obtain a copy of the License at
                     *
                     *    http://www.apache.org/licenses/LICENSE-2.0
                     *
                     * Unless required by applicable law or agreed to in writing, software
                     * distributed under the License is distributed on an "AS IS" BASIS,
                     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
                     * See the License for the specific language governing permissions and
                     * limitations under the License.
                     */
                    pragma solidity ^0.8.0;
                    library AddressAliasHelper {
                        uint160 constant offset = uint160(0x1111000000000000000000000000000000001111);
                        /// @notice Utility function that converts the address in the L1 that submitted a tx to
                        /// the inbox to the msg.sender viewed in the L2
                        /// @param l1Address the address in the L1 that triggered the tx to L2
                        /// @return l2Address L2 address as viewed in msg.sender
                        function applyL1ToL2Alias(address l1Address) internal pure returns (address l2Address) {
                            unchecked {
                                l2Address = address(uint160(l1Address) + offset);
                            }
                        }
                        /// @notice Utility function that converts the msg.sender viewed in the L2 to the
                        /// address in the L1 that submitted a tx to the inbox
                        /// @param l2Address L2 address as viewed in msg.sender
                        /// @return l1Address the address in the L1 that triggered the tx to L2
                        function undoL1ToL2Alias(address l2Address) internal pure returns (address l1Address) {
                            unchecked {
                                l1Address = address(uint160(l2Address) - offset);
                            }
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    pragma solidity 0.8.15;
                    import { Initializable } from "@openzeppelin/contracts/proxy/utils/Initializable.sol";
                    import { Math } from "@openzeppelin/contracts/utils/math/Math.sol";
                    import { Burn } from "../libraries/Burn.sol";
                    import { Arithmetic } from "../libraries/Arithmetic.sol";
                    /// @custom:upgradeable
                    /// @title ResourceMetering
                    /// @notice ResourceMetering implements an EIP-1559 style resource metering system where pricing
                    ///         updates automatically based on current demand.
                    abstract contract ResourceMetering is Initializable {
                        /// @notice Represents the various parameters that control the way in which resources are
                        ///         metered. Corresponds to the EIP-1559 resource metering system.
                        /// @custom:field prevBaseFee   Base fee from the previous block(s).
                        /// @custom:field prevBoughtGas Amount of gas bought so far in the current block.
                        /// @custom:field prevBlockNum  Last block number that the base fee was updated.
                        struct ResourceParams {
                            uint128 prevBaseFee;
                            uint64 prevBoughtGas;
                            uint64 prevBlockNum;
                        }
                        /// @notice Represents the configuration for the EIP-1559 based curve for the deposit gas
                        ///         market. These values should be set with care as it is possible to set them in
                        ///         a way that breaks the deposit gas market. The target resource limit is defined as
                        ///         maxResourceLimit / elasticityMultiplier. This struct was designed to fit within a
                        ///         single word. There is additional space for additions in the future.
                        /// @custom:field maxResourceLimit             Represents the maximum amount of deposit gas that
                        ///                                            can be purchased per block.
                        /// @custom:field elasticityMultiplier         Determines the target resource limit along with
                        ///                                            the resource limit.
                        /// @custom:field baseFeeMaxChangeDenominator  Determines max change on fee per block.
                        /// @custom:field minimumBaseFee               The min deposit base fee, it is clamped to this
                        ///                                            value.
                        /// @custom:field systemTxMaxGas               The amount of gas supplied to the system
                        ///                                            transaction. This should be set to the same
                        ///                                            number that the op-node sets as the gas limit
                        ///                                            for the system transaction.
                        /// @custom:field maximumBaseFee               The max deposit base fee, it is clamped to this
                        ///                                            value.
                        struct ResourceConfig {
                            uint32 maxResourceLimit;
                            uint8 elasticityMultiplier;
                            uint8 baseFeeMaxChangeDenominator;
                            uint32 minimumBaseFee;
                            uint32 systemTxMaxGas;
                            uint128 maximumBaseFee;
                        }
                        /// @notice EIP-1559 style gas parameters.
                        ResourceParams public params;
                        /// @notice Reserve extra slots (to a total of 50) in the storage layout for future upgrades.
                        uint256[48] private __gap;
                        /// @notice Meters access to a function based an amount of a requested resource.
                        /// @param _amount Amount of the resource requested.
                        modifier metered(uint64 _amount) {
                            // Record initial gas amount so we can refund for it later.
                            uint256 initialGas = gasleft();
                            // Run the underlying function.
                            _;
                            // Run the metering function.
                            _metered(_amount, initialGas);
                        }
                        /// @notice An internal function that holds all of the logic for metering a resource.
                        /// @param _amount     Amount of the resource requested.
                        /// @param _initialGas The amount of gas before any modifier execution.
                        function _metered(uint64 _amount, uint256 _initialGas) internal {
                            // Update block number and base fee if necessary.
                            uint256 blockDiff = block.number - params.prevBlockNum;
                            ResourceConfig memory config = _resourceConfig();
                            int256 targetResourceLimit = int256(uint256(config.maxResourceLimit)) /
                                int256(uint256(config.elasticityMultiplier));
                            if (blockDiff > 0) {
                                // Handle updating EIP-1559 style gas parameters. We use EIP-1559 to restrict the rate
                                // at which deposits can be created and therefore limit the potential for deposits to
                                // spam the L2 system. Fee scheme is very similar to EIP-1559 with minor changes.
                                int256 gasUsedDelta = int256(uint256(params.prevBoughtGas)) - targetResourceLimit;
                                int256 baseFeeDelta = (int256(uint256(params.prevBaseFee)) * gasUsedDelta) /
                                    (targetResourceLimit * int256(uint256(config.baseFeeMaxChangeDenominator)));
                                // Update base fee by adding the base fee delta and clamp the resulting value between
                                // min and max.
                                int256 newBaseFee = Arithmetic.clamp({
                                    _value: int256(uint256(params.prevBaseFee)) + baseFeeDelta,
                                    _min: int256(uint256(config.minimumBaseFee)),
                                    _max: int256(uint256(config.maximumBaseFee))
                                });
                                // If we skipped more than one block, we also need to account for every empty block.
                                // Empty block means there was no demand for deposits in that block, so we should
                                // reflect this lack of demand in the fee.
                                if (blockDiff > 1) {
                                    // Update the base fee by repeatedly applying the exponent 1-(1/change_denominator)
                                    // blockDiff - 1 times. Simulates multiple empty blocks. Clamp the resulting value
                                    // between min and max.
                                    newBaseFee = Arithmetic.clamp({
                                        _value: Arithmetic.cdexp({
                                            _coefficient: newBaseFee,
                                            _denominator: int256(uint256(config.baseFeeMaxChangeDenominator)),
                                            _exponent: int256(blockDiff - 1)
                                        }),
                                        _min: int256(uint256(config.minimumBaseFee)),
                                        _max: int256(uint256(config.maximumBaseFee))
                                    });
                                }
                                // Update new base fee, reset bought gas, and update block number.
                                params.prevBaseFee = uint128(uint256(newBaseFee));
                                params.prevBoughtGas = 0;
                                params.prevBlockNum = uint64(block.number);
                            }
                            // Make sure we can actually buy the resource amount requested by the user.
                            params.prevBoughtGas += _amount;
                            require(
                                int256(uint256(params.prevBoughtGas)) <= int256(uint256(config.maxResourceLimit)),
                                "ResourceMetering: cannot buy more gas than available gas limit"
                            );
                            // Determine the amount of ETH to be paid.
                            uint256 resourceCost = uint256(_amount) * uint256(params.prevBaseFee);
                            // We currently charge for this ETH amount as an L1 gas burn, so we convert the ETH amount
                            // into gas by dividing by the L1 base fee. We assume a minimum base fee of 1 gwei to avoid
                            // division by zero for L1s that don't support 1559 or to avoid excessive gas burns during
                            // periods of extremely low L1 demand. One-day average gas fee hasn't dipped below 1 gwei
                            // during any 1 day period in the last 5 years, so should be fine.
                            uint256 gasCost = resourceCost / Math.max(block.basefee, 1 gwei);
                            // Give the user a refund based on the amount of gas they used to do all of the work up to
                            // this point. Since we're at the end of the modifier, this should be pretty accurate. Acts
                            // effectively like a dynamic stipend (with a minimum value).
                            uint256 usedGas = _initialGas - gasleft();
                            if (gasCost > usedGas) {
                                Burn.gas(gasCost - usedGas);
                            }
                        }
                        /// @notice Virtual function that returns the resource config.
                        ///         Contracts that inherit this contract must implement this function.
                        /// @return ResourceConfig
                        function _resourceConfig() internal virtual returns (ResourceConfig memory);
                        /// @notice Sets initial resource parameter values.
                        ///         This function must either be called by the initializer function of an upgradeable
                        ///         child contract.
                        // solhint-disable-next-line func-name-mixedcase
                        function __ResourceMetering_init() internal onlyInitializing {
                            params = ResourceParams({
                                prevBaseFee: 1 gwei,
                                prevBoughtGas: 0,
                                prevBlockNum: uint64(block.number)
                            });
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    pragma solidity ^0.8.0;
                    import { Strings } from "@openzeppelin/contracts/utils/Strings.sol";
                    /// @title Semver
                    /// @notice Semver is a simple contract for managing contract versions.
                    contract Semver {
                        /// @notice Contract version number (major).
                        uint256 private immutable MAJOR_VERSION;
                        /// @notice Contract version number (minor).
                        uint256 private immutable MINOR_VERSION;
                        /// @notice Contract version number (patch).
                        uint256 private immutable PATCH_VERSION;
                        /// @param _major Version number (major).
                        /// @param _minor Version number (minor).
                        /// @param _patch Version number (patch).
                        constructor(
                            uint256 _major,
                            uint256 _minor,
                            uint256 _patch
                        ) {
                            MAJOR_VERSION = _major;
                            MINOR_VERSION = _minor;
                            PATCH_VERSION = _patch;
                        }
                        /// @notice Returns the full semver contract version.
                        /// @return Semver contract version as a string.
                        function version() public view returns (string memory) {
                            return
                                string(
                                    abi.encodePacked(
                                        Strings.toString(MAJOR_VERSION),
                                        ".",
                                        Strings.toString(MINOR_VERSION),
                                        ".",
                                        Strings.toString(PATCH_VERSION)
                                    )
                                );
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    // OpenZeppelin Contracts (last updated v4.7.0) (utils/Address.sol)
                    pragma solidity ^0.8.1;
                    /**
                     * @dev Collection of functions related to the address type
                     */
                    library Address {
                        /**
                         * @dev Returns true if `account` is a contract.
                         *
                         * [IMPORTANT]
                         * ====
                         * It is unsafe to assume that an address for which this function returns
                         * false is an externally-owned account (EOA) and not a contract.
                         *
                         * Among others, `isContract` will return false for the following
                         * types of addresses:
                         *
                         *  - an externally-owned account
                         *  - a contract in construction
                         *  - an address where a contract will be created
                         *  - an address where a contract lived, but was destroyed
                         * ====
                         *
                         * [IMPORTANT]
                         * ====
                         * You shouldn't rely on `isContract` to protect against flash loan attacks!
                         *
                         * Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets
                         * like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract
                         * constructor.
                         * ====
                         */
                        function isContract(address account) internal view returns (bool) {
                            // This method relies on extcodesize/address.code.length, which returns 0
                            // for contracts in construction, since the code is only stored at the end
                            // of the constructor execution.
                            return account.code.length > 0;
                        }
                        /**
                         * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
                         * `recipient`, forwarding all available gas and reverting on errors.
                         *
                         * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
                         * of certain opcodes, possibly making contracts go over the 2300 gas limit
                         * imposed by `transfer`, making them unable to receive funds via
                         * `transfer`. {sendValue} removes this limitation.
                         *
                         * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
                         *
                         * IMPORTANT: because control is transferred to `recipient`, care must be
                         * taken to not create reentrancy vulnerabilities. Consider using
                         * {ReentrancyGuard} or the
                         * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
                         */
                        function sendValue(address payable recipient, uint256 amount) internal {
                            require(address(this).balance >= amount, "Address: insufficient balance");
                            (bool success, ) = recipient.call{value: amount}("");
                            require(success, "Address: unable to send value, recipient may have reverted");
                        }
                        /**
                         * @dev Performs a Solidity function call using a low level `call`. A
                         * plain `call` is an unsafe replacement for a function call: use this
                         * function instead.
                         *
                         * If `target` reverts with a revert reason, it is bubbled up by this
                         * function (like regular Solidity function calls).
                         *
                         * Returns the raw returned data. To convert to the expected return value,
                         * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
                         *
                         * Requirements:
                         *
                         * - `target` must be a contract.
                         * - calling `target` with `data` must not revert.
                         *
                         * _Available since v3.1._
                         */
                        function functionCall(address target, bytes memory data) internal returns (bytes memory) {
                            return functionCall(target, data, "Address: low-level call failed");
                        }
                        /**
                         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
                         * `errorMessage` as a fallback revert reason when `target` reverts.
                         *
                         * _Available since v3.1._
                         */
                        function functionCall(
                            address target,
                            bytes memory data,
                            string memory errorMessage
                        ) internal returns (bytes memory) {
                            return functionCallWithValue(target, data, 0, errorMessage);
                        }
                        /**
                         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
                         * but also transferring `value` wei to `target`.
                         *
                         * Requirements:
                         *
                         * - the calling contract must have an ETH balance of at least `value`.
                         * - the called Solidity function must be `payable`.
                         *
                         * _Available since v3.1._
                         */
                        function functionCallWithValue(
                            address target,
                            bytes memory data,
                            uint256 value
                        ) internal returns (bytes memory) {
                            return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
                        }
                        /**
                         * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
                         * with `errorMessage` as a fallback revert reason when `target` reverts.
                         *
                         * _Available since v3.1._
                         */
                        function functionCallWithValue(
                            address target,
                            bytes memory data,
                            uint256 value,
                            string memory errorMessage
                        ) internal returns (bytes memory) {
                            require(address(this).balance >= value, "Address: insufficient balance for call");
                            require(isContract(target), "Address: call to non-contract");
                            (bool success, bytes memory returndata) = target.call{value: value}(data);
                            return verifyCallResult(success, returndata, errorMessage);
                        }
                        /**
                         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
                         * but performing a static call.
                         *
                         * _Available since v3.3._
                         */
                        function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
                            return functionStaticCall(target, data, "Address: low-level static call failed");
                        }
                        /**
                         * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
                         * but performing a static call.
                         *
                         * _Available since v3.3._
                         */
                        function functionStaticCall(
                            address target,
                            bytes memory data,
                            string memory errorMessage
                        ) internal view returns (bytes memory) {
                            require(isContract(target), "Address: static call to non-contract");
                            (bool success, bytes memory returndata) = target.staticcall(data);
                            return verifyCallResult(success, returndata, errorMessage);
                        }
                        /**
                         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
                         * but performing a delegate call.
                         *
                         * _Available since v3.4._
                         */
                        function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
                            return functionDelegateCall(target, data, "Address: low-level delegate call failed");
                        }
                        /**
                         * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
                         * but performing a delegate call.
                         *
                         * _Available since v3.4._
                         */
                        function functionDelegateCall(
                            address target,
                            bytes memory data,
                            string memory errorMessage
                        ) internal returns (bytes memory) {
                            require(isContract(target), "Address: delegate call to non-contract");
                            (bool success, bytes memory returndata) = target.delegatecall(data);
                            return verifyCallResult(success, returndata, errorMessage);
                        }
                        /**
                         * @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the
                         * revert reason using the provided one.
                         *
                         * _Available since v4.3._
                         */
                        function verifyCallResult(
                            bool success,
                            bytes memory returndata,
                            string memory errorMessage
                        ) internal pure returns (bytes memory) {
                            if (success) {
                                return returndata;
                            } else {
                                // Look for revert reason and bubble it up if present
                                if (returndata.length > 0) {
                                    // The easiest way to bubble the revert reason is using memory via assembly
                                    /// @solidity memory-safe-assembly
                                    assembly {
                                        let returndata_size := mload(returndata)
                                        revert(add(32, returndata), returndata_size)
                                    }
                                } else {
                                    revert(errorMessage);
                                }
                            }
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    // OpenZeppelin Contracts (last updated v4.7.0) (access/Ownable.sol)
                    pragma solidity ^0.8.0;
                    import "../utils/ContextUpgradeable.sol";
                    import "../proxy/utils/Initializable.sol";
                    /**
                     * @dev Contract module which provides a basic access control mechanism, where
                     * there is an account (an owner) that can be granted exclusive access to
                     * specific functions.
                     *
                     * By default, the owner account will be the one that deploys the contract. This
                     * can later be changed with {transferOwnership}.
                     *
                     * This module is used through inheritance. It will make available the modifier
                     * `onlyOwner`, which can be applied to your functions to restrict their use to
                     * the owner.
                     */
                    abstract contract OwnableUpgradeable is Initializable, ContextUpgradeable {
                        address private _owner;
                        event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
                        /**
                         * @dev Initializes the contract setting the deployer as the initial owner.
                         */
                        function __Ownable_init() internal onlyInitializing {
                            __Ownable_init_unchained();
                        }
                        function __Ownable_init_unchained() internal onlyInitializing {
                            _transferOwnership(_msgSender());
                        }
                        /**
                         * @dev Throws if called by any account other than the owner.
                         */
                        modifier onlyOwner() {
                            _checkOwner();
                            _;
                        }
                        /**
                         * @dev Returns the address of the current owner.
                         */
                        function owner() public view virtual returns (address) {
                            return _owner;
                        }
                        /**
                         * @dev Throws if the sender is not the owner.
                         */
                        function _checkOwner() internal view virtual {
                            require(owner() == _msgSender(), "Ownable: caller is not the owner");
                        }
                        /**
                         * @dev Leaves the contract without owner. It will not be possible to call
                         * `onlyOwner` functions anymore. Can only be called by the current owner.
                         *
                         * NOTE: Renouncing ownership will leave the contract without an owner,
                         * thereby removing any functionality that is only available to the owner.
                         */
                        function renounceOwnership() public virtual onlyOwner {
                            _transferOwnership(address(0));
                        }
                        /**
                         * @dev Transfers ownership of the contract to a new account (`newOwner`).
                         * Can only be called by the current owner.
                         */
                        function transferOwnership(address newOwner) public virtual onlyOwner {
                            require(newOwner != address(0), "Ownable: new owner is the zero address");
                            _transferOwnership(newOwner);
                        }
                        /**
                         * @dev Transfers ownership of the contract to a new account (`newOwner`).
                         * Internal function without access restriction.
                         */
                        function _transferOwnership(address newOwner) internal virtual {
                            address oldOwner = _owner;
                            _owner = newOwner;
                            emit OwnershipTransferred(oldOwner, newOwner);
                        }
                        /**
                         * @dev This empty reserved space is put in place to allow future versions to add new
                         * variables without shifting down storage in the inheritance chain.
                         * See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
                         */
                        uint256[49] private __gap;
                    }
                    // SPDX-License-Identifier: MIT
                    pragma solidity ^0.8.0;
                    import { Types } from "./Types.sol";
                    import { Hashing } from "./Hashing.sol";
                    import { RLPWriter } from "./rlp/RLPWriter.sol";
                    /// @title Encoding
                    /// @notice Encoding handles Optimism's various different encoding schemes.
                    library Encoding {
                        /// @notice RLP encodes the L2 transaction that would be generated when a given deposit is sent
                        ///         to the L2 system. Useful for searching for a deposit in the L2 system. The
                        ///         transaction is prefixed with 0x7e to identify its EIP-2718 type.
                        /// @param _tx User deposit transaction to encode.
                        /// @return RLP encoded L2 deposit transaction.
                        function encodeDepositTransaction(Types.UserDepositTransaction memory _tx)
                            internal
                            pure
                            returns (bytes memory)
                        {
                            bytes32 source = Hashing.hashDepositSource(_tx.l1BlockHash, _tx.logIndex);
                            bytes[] memory raw = new bytes[](8);
                            raw[0] = RLPWriter.writeBytes(abi.encodePacked(source));
                            raw[1] = RLPWriter.writeAddress(_tx.from);
                            raw[2] = _tx.isCreation ? RLPWriter.writeBytes("") : RLPWriter.writeAddress(_tx.to);
                            raw[3] = RLPWriter.writeUint(_tx.mint);
                            raw[4] = RLPWriter.writeUint(_tx.value);
                            raw[5] = RLPWriter.writeUint(uint256(_tx.gasLimit));
                            raw[6] = RLPWriter.writeBool(false);
                            raw[7] = RLPWriter.writeBytes(_tx.data);
                            return abi.encodePacked(uint8(0x7e), RLPWriter.writeList(raw));
                        }
                        /// @notice Encodes the cross domain message based on the version that is encoded into the
                        ///         message nonce.
                        /// @param _nonce    Message nonce with version encoded into the first two bytes.
                        /// @param _sender   Address of the sender of the message.
                        /// @param _target   Address of the target of the message.
                        /// @param _value    ETH value to send to the target.
                        /// @param _gasLimit Gas limit to use for the message.
                        /// @param _data     Data to send with the message.
                        /// @return Encoded cross domain message.
                        function encodeCrossDomainMessage(
                            uint256 _nonce,
                            address _sender,
                            address _target,
                            uint256 _value,
                            uint256 _gasLimit,
                            bytes memory _data
                        ) internal pure returns (bytes memory) {
                            (, uint16 version) = decodeVersionedNonce(_nonce);
                            if (version == 0) {
                                return encodeCrossDomainMessageV0(_target, _sender, _data, _nonce);
                            } else if (version == 1) {
                                return encodeCrossDomainMessageV1(_nonce, _sender, _target, _value, _gasLimit, _data);
                            } else {
                                revert("Encoding: unknown cross domain message version");
                            }
                        }
                        /// @notice Encodes a cross domain message based on the V0 (legacy) encoding.
                        /// @param _target Address of the target of the message.
                        /// @param _sender Address of the sender of the message.
                        /// @param _data   Data to send with the message.
                        /// @param _nonce  Message nonce.
                        /// @return Encoded cross domain message.
                        function encodeCrossDomainMessageV0(
                            address _target,
                            address _sender,
                            bytes memory _data,
                            uint256 _nonce
                        ) internal pure returns (bytes memory) {
                            return
                                abi.encodeWithSignature(
                                    "relayMessage(address,address,bytes,uint256)",
                                    _target,
                                    _sender,
                                    _data,
                                    _nonce
                                );
                        }
                        /// @notice Encodes a cross domain message based on the V1 (current) encoding.
                        /// @param _nonce    Message nonce.
                        /// @param _sender   Address of the sender of the message.
                        /// @param _target   Address of the target of the message.
                        /// @param _value    ETH value to send to the target.
                        /// @param _gasLimit Gas limit to use for the message.
                        /// @param _data     Data to send with the message.
                        /// @return Encoded cross domain message.
                        function encodeCrossDomainMessageV1(
                            uint256 _nonce,
                            address _sender,
                            address _target,
                            uint256 _value,
                            uint256 _gasLimit,
                            bytes memory _data
                        ) internal pure returns (bytes memory) {
                            return
                                abi.encodeWithSignature(
                                    "relayMessage(uint256,address,address,uint256,uint256,bytes)",
                                    _nonce,
                                    _sender,
                                    _target,
                                    _value,
                                    _gasLimit,
                                    _data
                                );
                        }
                        /// @notice Adds a version number into the first two bytes of a message nonce.
                        /// @param _nonce   Message nonce to encode into.
                        /// @param _version Version number to encode into the message nonce.
                        /// @return Message nonce with version encoded into the first two bytes.
                        function encodeVersionedNonce(uint240 _nonce, uint16 _version) internal pure returns (uint256) {
                            uint256 nonce;
                            assembly {
                                nonce := or(shl(240, _version), _nonce)
                            }
                            return nonce;
                        }
                        /// @notice Pulls the version out of a version-encoded nonce.
                        /// @param _nonce Message nonce with version encoded into the first two bytes.
                        /// @return Nonce without encoded version.
                        /// @return Version of the message.
                        function decodeVersionedNonce(uint256 _nonce) internal pure returns (uint240, uint16) {
                            uint240 nonce;
                            uint16 version;
                            assembly {
                                nonce := and(_nonce, 0x0000ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff)
                                version := shr(240, _nonce)
                            }
                            return (nonce, version);
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    pragma solidity ^0.8.0;
                    import { Bytes } from "../Bytes.sol";
                    import { RLPReader } from "../rlp/RLPReader.sol";
                    /**
                     * @title MerkleTrie
                     * @notice MerkleTrie is a small library for verifying standard Ethereum Merkle-Patricia trie
                     *         inclusion proofs. By default, this library assumes a hexary trie. One can change the
                     *         trie radix constant to support other trie radixes.
                     */
                    library MerkleTrie {
                        /**
                         * @notice Struct representing a node in the trie.
                         *
                         * @custom:field encoded The RLP-encoded node.
                         * @custom:field decoded The RLP-decoded node.
                         */
                        struct TrieNode {
                            bytes encoded;
                            RLPReader.RLPItem[] decoded;
                        }
                        /**
                         * @notice Determines the number of elements per branch node.
                         */
                        uint256 internal constant TREE_RADIX = 16;
                        /**
                         * @notice Branch nodes have TREE_RADIX elements and one value element.
                         */
                        uint256 internal constant BRANCH_NODE_LENGTH = TREE_RADIX + 1;
                        /**
                         * @notice Leaf nodes and extension nodes have two elements, a `path` and a `value`.
                         */
                        uint256 internal constant LEAF_OR_EXTENSION_NODE_LENGTH = 2;
                        /**
                         * @notice Prefix for even-nibbled extension node paths.
                         */
                        uint8 internal constant PREFIX_EXTENSION_EVEN = 0;
                        /**
                         * @notice Prefix for odd-nibbled extension node paths.
                         */
                        uint8 internal constant PREFIX_EXTENSION_ODD = 1;
                        /**
                         * @notice Prefix for even-nibbled leaf node paths.
                         */
                        uint8 internal constant PREFIX_LEAF_EVEN = 2;
                        /**
                         * @notice Prefix for odd-nibbled leaf node paths.
                         */
                        uint8 internal constant PREFIX_LEAF_ODD = 3;
                        /**
                         * @notice Verifies a proof that a given key/value pair is present in the trie.
                         *
                         * @param _key   Key of the node to search for, as a hex string.
                         * @param _value Value of the node to search for, as a hex string.
                         * @param _proof Merkle trie inclusion proof for the desired node. Unlike traditional Merkle
                         *               trees, this proof is executed top-down and consists of a list of RLP-encoded
                         *               nodes that make a path down to the target node.
                         * @param _root  Known root of the Merkle trie. Used to verify that the included proof is
                         *               correctly constructed.
                         *
                         * @return Whether or not the proof is valid.
                         */
                        function verifyInclusionProof(
                            bytes memory _key,
                            bytes memory _value,
                            bytes[] memory _proof,
                            bytes32 _root
                        ) internal pure returns (bool) {
                            return Bytes.equal(_value, get(_key, _proof, _root));
                        }
                        /**
                         * @notice Retrieves the value associated with a given key.
                         *
                         * @param _key   Key to search for, as hex bytes.
                         * @param _proof Merkle trie inclusion proof for the key.
                         * @param _root  Known root of the Merkle trie.
                         *
                         * @return Value of the key if it exists.
                         */
                        function get(
                            bytes memory _key,
                            bytes[] memory _proof,
                            bytes32 _root
                        ) internal pure returns (bytes memory) {
                            require(_key.length > 0, "MerkleTrie: empty key");
                            TrieNode[] memory proof = _parseProof(_proof);
                            bytes memory key = Bytes.toNibbles(_key);
                            bytes memory currentNodeID = abi.encodePacked(_root);
                            uint256 currentKeyIndex = 0;
                            // Proof is top-down, so we start at the first element (root).
                            for (uint256 i = 0; i < proof.length; i++) {
                                TrieNode memory currentNode = proof[i];
                                // Key index should never exceed total key length or we'll be out of bounds.
                                require(
                                    currentKeyIndex <= key.length,
                                    "MerkleTrie: key index exceeds total key length"
                                );
                                if (currentKeyIndex == 0) {
                                    // First proof element is always the root node.
                                    require(
                                        Bytes.equal(abi.encodePacked(keccak256(currentNode.encoded)), currentNodeID),
                                        "MerkleTrie: invalid root hash"
                                    );
                                } else if (currentNode.encoded.length >= 32) {
                                    // Nodes 32 bytes or larger are hashed inside branch nodes.
                                    require(
                                        Bytes.equal(abi.encodePacked(keccak256(currentNode.encoded)), currentNodeID),
                                        "MerkleTrie: invalid large internal hash"
                                    );
                                } else {
                                    // Nodes smaller than 32 bytes aren't hashed.
                                    require(
                                        Bytes.equal(currentNode.encoded, currentNodeID),
                                        "MerkleTrie: invalid internal node hash"
                                    );
                                }
                                if (currentNode.decoded.length == BRANCH_NODE_LENGTH) {
                                    if (currentKeyIndex == key.length) {
                                        // Value is the last element of the decoded list (for branch nodes). There's
                                        // some ambiguity in the Merkle trie specification because bytes(0) is a
                                        // valid value to place into the trie, but for branch nodes bytes(0) can exist
                                        // even when the value wasn't explicitly placed there. Geth treats a value of
                                        // bytes(0) as "key does not exist" and so we do the same.
                                        bytes memory value = RLPReader.readBytes(currentNode.decoded[TREE_RADIX]);
                                        require(
                                            value.length > 0,
                                            "MerkleTrie: value length must be greater than zero (branch)"
                                        );
                                        // Extra proof elements are not allowed.
                                        require(
                                            i == proof.length - 1,
                                            "MerkleTrie: value node must be last node in proof (branch)"
                                        );
                                        return value;
                                    } else {
                                        // We're not at the end of the key yet.
                                        // Figure out what the next node ID should be and continue.
                                        uint8 branchKey = uint8(key[currentKeyIndex]);
                                        RLPReader.RLPItem memory nextNode = currentNode.decoded[branchKey];
                                        currentNodeID = _getNodeID(nextNode);
                                        currentKeyIndex += 1;
                                    }
                                } else if (currentNode.decoded.length == LEAF_OR_EXTENSION_NODE_LENGTH) {
                                    bytes memory path = _getNodePath(currentNode);
                                    uint8 prefix = uint8(path[0]);
                                    uint8 offset = 2 - (prefix % 2);
                                    bytes memory pathRemainder = Bytes.slice(path, offset);
                                    bytes memory keyRemainder = Bytes.slice(key, currentKeyIndex);
                                    uint256 sharedNibbleLength = _getSharedNibbleLength(pathRemainder, keyRemainder);
                                    // Whether this is a leaf node or an extension node, the path remainder MUST be a
                                    // prefix of the key remainder (or be equal to the key remainder) or the proof is
                                    // considered invalid.
                                    require(
                                        pathRemainder.length == sharedNibbleLength,
                                        "MerkleTrie: path remainder must share all nibbles with key"
                                    );
                                    if (prefix == PREFIX_LEAF_EVEN || prefix == PREFIX_LEAF_ODD) {
                                        // Prefix of 2 or 3 means this is a leaf node. For the leaf node to be valid,
                                        // the key remainder must be exactly equal to the path remainder. We already
                                        // did the necessary byte comparison, so it's more efficient here to check that
                                        // the key remainder length equals the shared nibble length, which implies
                                        // equality with the path remainder (since we already did the same check with
                                        // the path remainder and the shared nibble length).
                                        require(
                                            keyRemainder.length == sharedNibbleLength,
                                            "MerkleTrie: key remainder must be identical to path remainder"
                                        );
                                        // Our Merkle Trie is designed specifically for the purposes of the Ethereum
                                        // state trie. Empty values are not allowed in the state trie, so we can safely
                                        // say that if the value is empty, the key should not exist and the proof is
                                        // invalid.
                                        bytes memory value = RLPReader.readBytes(currentNode.decoded[1]);
                                        require(
                                            value.length > 0,
                                            "MerkleTrie: value length must be greater than zero (leaf)"
                                        );
                                        // Extra proof elements are not allowed.
                                        require(
                                            i == proof.length - 1,
                                            "MerkleTrie: value node must be last node in proof (leaf)"
                                        );
                                        return value;
                                    } else if (prefix == PREFIX_EXTENSION_EVEN || prefix == PREFIX_EXTENSION_ODD) {
                                        // Prefix of 0 or 1 means this is an extension node. We move onto the next node
                                        // in the proof and increment the key index by the length of the path remainder
                                        // which is equal to the shared nibble length.
                                        currentNodeID = _getNodeID(currentNode.decoded[1]);
                                        currentKeyIndex += sharedNibbleLength;
                                    } else {
                                        revert("MerkleTrie: received a node with an unknown prefix");
                                    }
                                } else {
                                    revert("MerkleTrie: received an unparseable node");
                                }
                            }
                            revert("MerkleTrie: ran out of proof elements");
                        }
                        /**
                         * @notice Parses an array of proof elements into a new array that contains both the original
                         *         encoded element and the RLP-decoded element.
                         *
                         * @param _proof Array of proof elements to parse.
                         *
                         * @return Proof parsed into easily accessible structs.
                         */
                        function _parseProof(bytes[] memory _proof) private pure returns (TrieNode[] memory) {
                            uint256 length = _proof.length;
                            TrieNode[] memory proof = new TrieNode[](length);
                            for (uint256 i = 0; i < length; ) {
                                proof[i] = TrieNode({ encoded: _proof[i], decoded: RLPReader.readList(_proof[i]) });
                                unchecked {
                                    ++i;
                                }
                            }
                            return proof;
                        }
                        /**
                         * @notice Picks out the ID for a node. Node ID is referred to as the "hash" within the
                         *         specification, but nodes < 32 bytes are not actually hashed.
                         *
                         * @param _node Node to pull an ID for.
                         *
                         * @return ID for the node, depending on the size of its contents.
                         */
                        function _getNodeID(RLPReader.RLPItem memory _node) private pure returns (bytes memory) {
                            return _node.length < 32 ? RLPReader.readRawBytes(_node) : RLPReader.readBytes(_node);
                        }
                        /**
                         * @notice Gets the path for a leaf or extension node.
                         *
                         * @param _node Node to get a path for.
                         *
                         * @return Node path, converted to an array of nibbles.
                         */
                        function _getNodePath(TrieNode memory _node) private pure returns (bytes memory) {
                            return Bytes.toNibbles(RLPReader.readBytes(_node.decoded[0]));
                        }
                        /**
                         * @notice Utility; determines the number of nibbles shared between two nibble arrays.
                         *
                         * @param _a First nibble array.
                         * @param _b Second nibble array.
                         *
                         * @return Number of shared nibbles.
                         */
                        function _getSharedNibbleLength(bytes memory _a, bytes memory _b)
                            private
                            pure
                            returns (uint256)
                        {
                            uint256 shared;
                            uint256 max = (_a.length < _b.length) ? _a.length : _b.length;
                            for (; shared < max && _a[shared] == _b[shared]; ) {
                                unchecked {
                                    ++shared;
                                }
                            }
                            return shared;
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    // OpenZeppelin Contracts (last updated v4.7.0) (utils/math/Math.sol)
                    pragma solidity ^0.8.0;
                    /**
                     * @dev Standard math utilities missing in the Solidity language.
                     */
                    library Math {
                        enum Rounding {
                            Down, // Toward negative infinity
                            Up, // Toward infinity
                            Zero // Toward zero
                        }
                        /**
                         * @dev Returns the largest of two numbers.
                         */
                        function max(uint256 a, uint256 b) internal pure returns (uint256) {
                            return a >= b ? a : b;
                        }
                        /**
                         * @dev Returns the smallest of two numbers.
                         */
                        function min(uint256 a, uint256 b) internal pure returns (uint256) {
                            return a < b ? a : b;
                        }
                        /**
                         * @dev Returns the average of two numbers. The result is rounded towards
                         * zero.
                         */
                        function average(uint256 a, uint256 b) internal pure returns (uint256) {
                            // (a + b) / 2 can overflow.
                            return (a & b) + (a ^ b) / 2;
                        }
                        /**
                         * @dev Returns the ceiling of the division of two numbers.
                         *
                         * This differs from standard division with `/` in that it rounds up instead
                         * of rounding down.
                         */
                        function ceilDiv(uint256 a, uint256 b) internal pure returns (uint256) {
                            // (a + b - 1) / b can overflow on addition, so we distribute.
                            return a == 0 ? 0 : (a - 1) / b + 1;
                        }
                        /**
                         * @notice Calculates floor(x * y / denominator) with full precision. Throws if result overflows a uint256 or denominator == 0
                         * @dev Original credit to Remco Bloemen under MIT license (https://xn--2-umb.com/21/muldiv)
                         * with further edits by Uniswap Labs also under MIT license.
                         */
                        function mulDiv(
                            uint256 x,
                            uint256 y,
                            uint256 denominator
                        ) internal pure returns (uint256 result) {
                            unchecked {
                                // 512-bit multiply [prod1 prod0] = x * y. Compute the product mod 2^256 and mod 2^256 - 1, then use
                                // use the Chinese Remainder Theorem to reconstruct the 512 bit result. The result is stored in two 256
                                // variables such that product = prod1 * 2^256 + prod0.
                                uint256 prod0; // Least significant 256 bits of the product
                                uint256 prod1; // Most significant 256 bits of the product
                                assembly {
                                    let mm := mulmod(x, y, not(0))
                                    prod0 := mul(x, y)
                                    prod1 := sub(sub(mm, prod0), lt(mm, prod0))
                                }
                                // Handle non-overflow cases, 256 by 256 division.
                                if (prod1 == 0) {
                                    return prod0 / denominator;
                                }
                                // Make sure the result is less than 2^256. Also prevents denominator == 0.
                                require(denominator > prod1);
                                ///////////////////////////////////////////////
                                // 512 by 256 division.
                                ///////////////////////////////////////////////
                                // Make division exact by subtracting the remainder from [prod1 prod0].
                                uint256 remainder;
                                assembly {
                                    // Compute remainder using mulmod.
                                    remainder := mulmod(x, y, denominator)
                                    // Subtract 256 bit number from 512 bit number.
                                    prod1 := sub(prod1, gt(remainder, prod0))
                                    prod0 := sub(prod0, remainder)
                                }
                                // Factor powers of two out of denominator and compute largest power of two divisor of denominator. Always >= 1.
                                // See https://cs.stackexchange.com/q/138556/92363.
                                // Does not overflow because the denominator cannot be zero at this stage in the function.
                                uint256 twos = denominator & (~denominator + 1);
                                assembly {
                                    // Divide denominator by twos.
                                    denominator := div(denominator, twos)
                                    // Divide [prod1 prod0] by twos.
                                    prod0 := div(prod0, twos)
                                    // Flip twos such that it is 2^256 / twos. If twos is zero, then it becomes one.
                                    twos := add(div(sub(0, twos), twos), 1)
                                }
                                // Shift in bits from prod1 into prod0.
                                prod0 |= prod1 * twos;
                                // Invert denominator mod 2^256. Now that denominator is an odd number, it has an inverse modulo 2^256 such
                                // that denominator * inv = 1 mod 2^256. Compute the inverse by starting with a seed that is correct for
                                // four bits. That is, denominator * inv = 1 mod 2^4.
                                uint256 inverse = (3 * denominator) ^ 2;
                                // Use the Newton-Raphson iteration to improve the precision. Thanks to Hensel's lifting lemma, this also works
                                // in modular arithmetic, doubling the correct bits in each step.
                                inverse *= 2 - denominator * inverse; // inverse mod 2^8
                                inverse *= 2 - denominator * inverse; // inverse mod 2^16
                                inverse *= 2 - denominator * inverse; // inverse mod 2^32
                                inverse *= 2 - denominator * inverse; // inverse mod 2^64
                                inverse *= 2 - denominator * inverse; // inverse mod 2^128
                                inverse *= 2 - denominator * inverse; // inverse mod 2^256
                                // Because the division is now exact we can divide by multiplying with the modular inverse of denominator.
                                // This will give us the correct result modulo 2^256. Since the preconditions guarantee that the outcome is
                                // less than 2^256, this is the final result. We don't need to compute the high bits of the result and prod1
                                // is no longer required.
                                result = prod0 * inverse;
                                return result;
                            }
                        }
                        /**
                         * @notice Calculates x * y / denominator with full precision, following the selected rounding direction.
                         */
                        function mulDiv(
                            uint256 x,
                            uint256 y,
                            uint256 denominator,
                            Rounding rounding
                        ) internal pure returns (uint256) {
                            uint256 result = mulDiv(x, y, denominator);
                            if (rounding == Rounding.Up && mulmod(x, y, denominator) > 0) {
                                result += 1;
                            }
                            return result;
                        }
                        /**
                         * @dev Returns the square root of a number. It the number is not a perfect square, the value is rounded down.
                         *
                         * Inspired by Henry S. Warren, Jr.'s "Hacker's Delight" (Chapter 11).
                         */
                        function sqrt(uint256 a) internal pure returns (uint256) {
                            if (a == 0) {
                                return 0;
                            }
                            // For our first guess, we get the biggest power of 2 which is smaller than the square root of the target.
                            // We know that the "msb" (most significant bit) of our target number `a` is a power of 2 such that we have
                            // `msb(a) <= a < 2*msb(a)`.
                            // We also know that `k`, the position of the most significant bit, is such that `msb(a) = 2**k`.
                            // This gives `2**k < a <= 2**(k+1)` → `2**(k/2) <= sqrt(a) < 2 ** (k/2+1)`.
                            // Using an algorithm similar to the msb conmputation, we are able to compute `result = 2**(k/2)` which is a
                            // good first aproximation of `sqrt(a)` with at least 1 correct bit.
                            uint256 result = 1;
                            uint256 x = a;
                            if (x >> 128 > 0) {
                                x >>= 128;
                                result <<= 64;
                            }
                            if (x >> 64 > 0) {
                                x >>= 64;
                                result <<= 32;
                            }
                            if (x >> 32 > 0) {
                                x >>= 32;
                                result <<= 16;
                            }
                            if (x >> 16 > 0) {
                                x >>= 16;
                                result <<= 8;
                            }
                            if (x >> 8 > 0) {
                                x >>= 8;
                                result <<= 4;
                            }
                            if (x >> 4 > 0) {
                                x >>= 4;
                                result <<= 2;
                            }
                            if (x >> 2 > 0) {
                                result <<= 1;
                            }
                            // At this point `result` is an estimation with one bit of precision. We know the true value is a uint128,
                            // since it is the square root of a uint256. Newton's method converges quadratically (precision doubles at
                            // every iteration). We thus need at most 7 iteration to turn our partial result with one bit of precision
                            // into the expected uint128 result.
                            unchecked {
                                result = (result + a / result) >> 1;
                                result = (result + a / result) >> 1;
                                result = (result + a / result) >> 1;
                                result = (result + a / result) >> 1;
                                result = (result + a / result) >> 1;
                                result = (result + a / result) >> 1;
                                result = (result + a / result) >> 1;
                                return min(result, a / result);
                            }
                        }
                        /**
                         * @notice Calculates sqrt(a), following the selected rounding direction.
                         */
                        function sqrt(uint256 a, Rounding rounding) internal pure returns (uint256) {
                            uint256 result = sqrt(a);
                            if (rounding == Rounding.Up && result * result < a) {
                                result += 1;
                            }
                            return result;
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    pragma solidity 0.8.15;
                    /// @title Burn
                    /// @notice Utilities for burning stuff.
                    library Burn {
                        /// @notice Burns a given amount of ETH.
                        /// @param _amount Amount of ETH to burn.
                        function eth(uint256 _amount) internal {
                            new Burner{ value: _amount }();
                        }
                        /// @notice Burns a given amount of gas.
                        /// @param _amount Amount of gas to burn.
                        function gas(uint256 _amount) internal view {
                            uint256 i = 0;
                            uint256 initialGas = gasleft();
                            while (initialGas - gasleft() < _amount) {
                                ++i;
                            }
                        }
                    }
                    /// @title Burner
                    /// @notice Burner self-destructs on creation and sends all ETH to itself, removing all ETH given to
                    ///         the contract from the circulating supply. Self-destructing is the only way to remove ETH
                    ///         from the circulating supply.
                    contract Burner {
                        constructor() payable {
                            selfdestruct(payable(address(this)));
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    pragma solidity 0.8.15;
                    import { SignedMath } from "@openzeppelin/contracts/utils/math/SignedMath.sol";
                    import { FixedPointMathLib } from "@rari-capital/solmate/src/utils/FixedPointMathLib.sol";
                    /// @title Arithmetic
                    /// @notice Even more math than before.
                    library Arithmetic {
                        /// @notice Clamps a value between a minimum and maximum.
                        /// @param _value The value to clamp.
                        /// @param _min   The minimum value.
                        /// @param _max   The maximum value.
                        /// @return The clamped value.
                        function clamp(
                            int256 _value,
                            int256 _min,
                            int256 _max
                        ) internal pure returns (int256) {
                            return SignedMath.min(SignedMath.max(_value, _min), _max);
                        }
                        /// @notice (c)oefficient (d)enominator (exp)onentiation function.
                        ///         Returns the result of: c * (1 - 1/d)^exp.
                        /// @param _coefficient Coefficient of the function.
                        /// @param _denominator Fractional denominator.
                        /// @param _exponent    Power function exponent.
                        /// @return Result of c * (1 - 1/d)^exp.
                        function cdexp(
                            int256 _coefficient,
                            int256 _denominator,
                            int256 _exponent
                        ) internal pure returns (int256) {
                            return
                                (_coefficient *
                                    (FixedPointMathLib.powWad(1e18 - (1e18 / _denominator), _exponent * 1e18))) / 1e18;
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    // OpenZeppelin Contracts (last updated v4.7.0) (utils/Strings.sol)
                    pragma solidity ^0.8.0;
                    /**
                     * @dev String operations.
                     */
                    library Strings {
                        bytes16 private constant _HEX_SYMBOLS = "0123456789abcdef";
                        uint8 private constant _ADDRESS_LENGTH = 20;
                        /**
                         * @dev Converts a `uint256` to its ASCII `string` decimal representation.
                         */
                        function toString(uint256 value) internal pure returns (string memory) {
                            // Inspired by OraclizeAPI's implementation - MIT licence
                            // https://github.com/oraclize/ethereum-api/blob/b42146b063c7d6ee1358846c198246239e9360e8/oraclizeAPI_0.4.25.sol
                            if (value == 0) {
                                return "0";
                            }
                            uint256 temp = value;
                            uint256 digits;
                            while (temp != 0) {
                                digits++;
                                temp /= 10;
                            }
                            bytes memory buffer = new bytes(digits);
                            while (value != 0) {
                                digits -= 1;
                                buffer[digits] = bytes1(uint8(48 + uint256(value % 10)));
                                value /= 10;
                            }
                            return string(buffer);
                        }
                        /**
                         * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation.
                         */
                        function toHexString(uint256 value) internal pure returns (string memory) {
                            if (value == 0) {
                                return "0x00";
                            }
                            uint256 temp = value;
                            uint256 length = 0;
                            while (temp != 0) {
                                length++;
                                temp >>= 8;
                            }
                            return toHexString(value, length);
                        }
                        /**
                         * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation with fixed length.
                         */
                        function toHexString(uint256 value, uint256 length) internal pure returns (string memory) {
                            bytes memory buffer = new bytes(2 * length + 2);
                            buffer[0] = "0";
                            buffer[1] = "x";
                            for (uint256 i = 2 * length + 1; i > 1; --i) {
                                buffer[i] = _HEX_SYMBOLS[value & 0xf];
                                value >>= 4;
                            }
                            require(value == 0, "Strings: hex length insufficient");
                            return string(buffer);
                        }
                        /**
                         * @dev Converts an `address` with fixed length of 20 bytes to its not checksummed ASCII `string` hexadecimal representation.
                         */
                        function toHexString(address addr) internal pure returns (string memory) {
                            return toHexString(uint256(uint160(addr)), _ADDRESS_LENGTH);
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    // OpenZeppelin Contracts v4.4.1 (utils/Context.sol)
                    pragma solidity ^0.8.0;
                    import "../proxy/utils/Initializable.sol";
                    /**
                     * @dev Provides information about the current execution context, including the
                     * sender of the transaction and its data. While these are generally available
                     * via msg.sender and msg.data, they should not be accessed in such a direct
                     * manner, since when dealing with meta-transactions the account sending and
                     * paying for execution may not be the actual sender (as far as an application
                     * is concerned).
                     *
                     * This contract is only required for intermediate, library-like contracts.
                     */
                    abstract contract ContextUpgradeable is Initializable {
                        function __Context_init() internal onlyInitializing {
                        }
                        function __Context_init_unchained() internal onlyInitializing {
                        }
                        function _msgSender() internal view virtual returns (address) {
                            return msg.sender;
                        }
                        function _msgData() internal view virtual returns (bytes calldata) {
                            return msg.data;
                        }
                        /**
                         * @dev This empty reserved space is put in place to allow future versions to add new
                         * variables without shifting down storage in the inheritance chain.
                         * See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
                         */
                        uint256[50] private __gap;
                    }
                    // SPDX-License-Identifier: MIT
                    // OpenZeppelin Contracts (last updated v4.7.0) (proxy/utils/Initializable.sol)
                    pragma solidity ^0.8.2;
                    import "../../utils/AddressUpgradeable.sol";
                    /**
                     * @dev This is a base contract to aid in writing upgradeable contracts, or any kind of contract that will be deployed
                     * behind a proxy. Since proxied contracts do not make use of a constructor, it's common to move constructor logic to an
                     * external initializer function, usually called `initialize`. It then becomes necessary to protect this initializer
                     * function so it can only be called once. The {initializer} modifier provided by this contract will have this effect.
                     *
                     * The initialization functions use a version number. Once a version number is used, it is consumed and cannot be
                     * reused. This mechanism prevents re-execution of each "step" but allows the creation of new initialization steps in
                     * case an upgrade adds a module that needs to be initialized.
                     *
                     * For example:
                     *
                     * [.hljs-theme-light.nopadding]
                     * ```
                     * contract MyToken is ERC20Upgradeable {
                     *     function initialize() initializer public {
                     *         __ERC20_init("MyToken", "MTK");
                     *     }
                     * }
                     * contract MyTokenV2 is MyToken, ERC20PermitUpgradeable {
                     *     function initializeV2() reinitializer(2) public {
                     *         __ERC20Permit_init("MyToken");
                     *     }
                     * }
                     * ```
                     *
                     * TIP: To avoid leaving the proxy in an uninitialized state, the initializer function should be called as early as
                     * possible by providing the encoded function call as the `_data` argument to {ERC1967Proxy-constructor}.
                     *
                     * CAUTION: When used with inheritance, manual care must be taken to not invoke a parent initializer twice, or to ensure
                     * that all initializers are idempotent. This is not verified automatically as constructors are by Solidity.
                     *
                     * [CAUTION]
                     * ====
                     * Avoid leaving a contract uninitialized.
                     *
                     * An uninitialized contract can be taken over by an attacker. This applies to both a proxy and its implementation
                     * contract, which may impact the proxy. To prevent the implementation contract from being used, you should invoke
                     * the {_disableInitializers} function in the constructor to automatically lock it when it is deployed:
                     *
                     * [.hljs-theme-light.nopadding]
                     * ```
                     * /// @custom:oz-upgrades-unsafe-allow constructor
                     * constructor() {
                     *     _disableInitializers();
                     * }
                     * ```
                     * ====
                     */
                    abstract contract Initializable {
                        /**
                         * @dev Indicates that the contract has been initialized.
                         * @custom:oz-retyped-from bool
                         */
                        uint8 private _initialized;
                        /**
                         * @dev Indicates that the contract is in the process of being initialized.
                         */
                        bool private _initializing;
                        /**
                         * @dev Triggered when the contract has been initialized or reinitialized.
                         */
                        event Initialized(uint8 version);
                        /**
                         * @dev A modifier that defines a protected initializer function that can be invoked at most once. In its scope,
                         * `onlyInitializing` functions can be used to initialize parent contracts. Equivalent to `reinitializer(1)`.
                         */
                        modifier initializer() {
                            bool isTopLevelCall = !_initializing;
                            require(
                                (isTopLevelCall && _initialized < 1) || (!AddressUpgradeable.isContract(address(this)) && _initialized == 1),
                                "Initializable: contract is already initialized"
                            );
                            _initialized = 1;
                            if (isTopLevelCall) {
                                _initializing = true;
                            }
                            _;
                            if (isTopLevelCall) {
                                _initializing = false;
                                emit Initialized(1);
                            }
                        }
                        /**
                         * @dev A modifier that defines a protected reinitializer function that can be invoked at most once, and only if the
                         * contract hasn't been initialized to a greater version before. In its scope, `onlyInitializing` functions can be
                         * used to initialize parent contracts.
                         *
                         * `initializer` is equivalent to `reinitializer(1)`, so a reinitializer may be used after the original
                         * initialization step. This is essential to configure modules that are added through upgrades and that require
                         * initialization.
                         *
                         * Note that versions can jump in increments greater than 1; this implies that if multiple reinitializers coexist in
                         * a contract, executing them in the right order is up to the developer or operator.
                         */
                        modifier reinitializer(uint8 version) {
                            require(!_initializing && _initialized < version, "Initializable: contract is already initialized");
                            _initialized = version;
                            _initializing = true;
                            _;
                            _initializing = false;
                            emit Initialized(version);
                        }
                        /**
                         * @dev Modifier to protect an initialization function so that it can only be invoked by functions with the
                         * {initializer} and {reinitializer} modifiers, directly or indirectly.
                         */
                        modifier onlyInitializing() {
                            require(_initializing, "Initializable: contract is not initializing");
                            _;
                        }
                        /**
                         * @dev Locks the contract, preventing any future reinitialization. This cannot be part of an initializer call.
                         * Calling this in the constructor of a contract will prevent that contract from being initialized or reinitialized
                         * to any version. It is recommended to use this to lock implementation contracts that are designed to be called
                         * through proxies.
                         */
                        function _disableInitializers() internal virtual {
                            require(!_initializing, "Initializable: contract is initializing");
                            if (_initialized < type(uint8).max) {
                                _initialized = type(uint8).max;
                                emit Initialized(type(uint8).max);
                            }
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    pragma solidity ^0.8.0;
                    /**
                     * @custom:attribution https://github.com/bakaoh/solidity-rlp-encode
                     * @title RLPWriter
                     * @author RLPWriter is a library for encoding Solidity types to RLP bytes. Adapted from Bakaoh's
                     *         RLPEncode library (https://github.com/bakaoh/solidity-rlp-encode) with minor
                     *         modifications to improve legibility.
                     */
                    library RLPWriter {
                        /**
                         * @notice RLP encodes a byte string.
                         *
                         * @param _in The byte string to encode.
                         *
                         * @return The RLP encoded string in bytes.
                         */
                        function writeBytes(bytes memory _in) internal pure returns (bytes memory) {
                            bytes memory encoded;
                            if (_in.length == 1 && uint8(_in[0]) < 128) {
                                encoded = _in;
                            } else {
                                encoded = abi.encodePacked(_writeLength(_in.length, 128), _in);
                            }
                            return encoded;
                        }
                        /**
                         * @notice RLP encodes a list of RLP encoded byte byte strings.
                         *
                         * @param _in The list of RLP encoded byte strings.
                         *
                         * @return The RLP encoded list of items in bytes.
                         */
                        function writeList(bytes[] memory _in) internal pure returns (bytes memory) {
                            bytes memory list = _flatten(_in);
                            return abi.encodePacked(_writeLength(list.length, 192), list);
                        }
                        /**
                         * @notice RLP encodes a string.
                         *
                         * @param _in The string to encode.
                         *
                         * @return The RLP encoded string in bytes.
                         */
                        function writeString(string memory _in) internal pure returns (bytes memory) {
                            return writeBytes(bytes(_in));
                        }
                        /**
                         * @notice RLP encodes an address.
                         *
                         * @param _in The address to encode.
                         *
                         * @return The RLP encoded address in bytes.
                         */
                        function writeAddress(address _in) internal pure returns (bytes memory) {
                            return writeBytes(abi.encodePacked(_in));
                        }
                        /**
                         * @notice RLP encodes a uint.
                         *
                         * @param _in The uint256 to encode.
                         *
                         * @return The RLP encoded uint256 in bytes.
                         */
                        function writeUint(uint256 _in) internal pure returns (bytes memory) {
                            return writeBytes(_toBinary(_in));
                        }
                        /**
                         * @notice RLP encodes a bool.
                         *
                         * @param _in The bool to encode.
                         *
                         * @return The RLP encoded bool in bytes.
                         */
                        function writeBool(bool _in) internal pure returns (bytes memory) {
                            bytes memory encoded = new bytes(1);
                            encoded[0] = (_in ? bytes1(0x01) : bytes1(0x80));
                            return encoded;
                        }
                        /**
                         * @notice Encode the first byte and then the `len` in binary form if `length` is more than 55.
                         *
                         * @param _len    The length of the string or the payload.
                         * @param _offset 128 if item is string, 192 if item is list.
                         *
                         * @return RLP encoded bytes.
                         */
                        function _writeLength(uint256 _len, uint256 _offset) private pure returns (bytes memory) {
                            bytes memory encoded;
                            if (_len < 56) {
                                encoded = new bytes(1);
                                encoded[0] = bytes1(uint8(_len) + uint8(_offset));
                            } else {
                                uint256 lenLen;
                                uint256 i = 1;
                                while (_len / i != 0) {
                                    lenLen++;
                                    i *= 256;
                                }
                                encoded = new bytes(lenLen + 1);
                                encoded[0] = bytes1(uint8(lenLen) + uint8(_offset) + 55);
                                for (i = 1; i <= lenLen; i++) {
                                    encoded[i] = bytes1(uint8((_len / (256**(lenLen - i))) % 256));
                                }
                            }
                            return encoded;
                        }
                        /**
                         * @notice Encode integer in big endian binary form with no leading zeroes.
                         *
                         * @param _x The integer to encode.
                         *
                         * @return RLP encoded bytes.
                         */
                        function _toBinary(uint256 _x) private pure returns (bytes memory) {
                            bytes memory b = abi.encodePacked(_x);
                            uint256 i = 0;
                            for (; i < 32; i++) {
                                if (b[i] != 0) {
                                    break;
                                }
                            }
                            bytes memory res = new bytes(32 - i);
                            for (uint256 j = 0; j < res.length; j++) {
                                res[j] = b[i++];
                            }
                            return res;
                        }
                        /**
                         * @custom:attribution https://github.com/Arachnid/solidity-stringutils
                         * @notice Copies a piece of memory to another location.
                         *
                         * @param _dest Destination location.
                         * @param _src  Source location.
                         * @param _len  Length of memory to copy.
                         */
                        function _memcpy(
                            uint256 _dest,
                            uint256 _src,
                            uint256 _len
                        ) private pure {
                            uint256 dest = _dest;
                            uint256 src = _src;
                            uint256 len = _len;
                            for (; len >= 32; len -= 32) {
                                assembly {
                                    mstore(dest, mload(src))
                                }
                                dest += 32;
                                src += 32;
                            }
                            uint256 mask;
                            unchecked {
                                mask = 256**(32 - len) - 1;
                            }
                            assembly {
                                let srcpart := and(mload(src), not(mask))
                                let destpart := and(mload(dest), mask)
                                mstore(dest, or(destpart, srcpart))
                            }
                        }
                        /**
                         * @custom:attribution https://github.com/sammayo/solidity-rlp-encoder
                         * @notice Flattens a list of byte strings into one byte string.
                         *
                         * @param _list List of byte strings to flatten.
                         *
                         * @return The flattened byte string.
                         */
                        function _flatten(bytes[] memory _list) private pure returns (bytes memory) {
                            if (_list.length == 0) {
                                return new bytes(0);
                            }
                            uint256 len;
                            uint256 i = 0;
                            for (; i < _list.length; i++) {
                                len += _list[i].length;
                            }
                            bytes memory flattened = new bytes(len);
                            uint256 flattenedPtr;
                            assembly {
                                flattenedPtr := add(flattened, 0x20)
                            }
                            for (i = 0; i < _list.length; i++) {
                                bytes memory item = _list[i];
                                uint256 listPtr;
                                assembly {
                                    listPtr := add(item, 0x20)
                                }
                                _memcpy(flattenedPtr, listPtr, item.length);
                                flattenedPtr += _list[i].length;
                            }
                            return flattened;
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    pragma solidity ^0.8.0;
                    /// @title Bytes
                    /// @notice Bytes is a library for manipulating byte arrays.
                    library Bytes {
                        /// @custom:attribution https://github.com/GNSPS/solidity-bytes-utils
                        /// @notice Slices a byte array with a given starting index and length. Returns a new byte array
                        ///         as opposed to a pointer to the original array. Will throw if trying to slice more
                        ///         bytes than exist in the array.
                        /// @param _bytes Byte array to slice.
                        /// @param _start Starting index of the slice.
                        /// @param _length Length of the slice.
                        /// @return Slice of the input byte array.
                        function slice(
                            bytes memory _bytes,
                            uint256 _start,
                            uint256 _length
                        ) internal pure returns (bytes memory) {
                            unchecked {
                                require(_length + 31 >= _length, "slice_overflow");
                                require(_start + _length >= _start, "slice_overflow");
                                require(_bytes.length >= _start + _length, "slice_outOfBounds");
                            }
                            bytes memory tempBytes;
                            assembly {
                                switch iszero(_length)
                                case 0 {
                                    // Get a location of some free memory and store it in tempBytes as
                                    // Solidity does for memory variables.
                                    tempBytes := mload(0x40)
                                    // The first word of the slice result is potentially a partial
                                    // word read from the original array. To read it, we calculate
                                    // the length of that partial word and start copying that many
                                    // bytes into the array. The first word we copy will start with
                                    // data we don't care about, but the last `lengthmod` bytes will
                                    // land at the beginning of the contents of the new array. When
                                    // we're done copying, we overwrite the full first word with
                                    // the actual length of the slice.
                                    let lengthmod := and(_length, 31)
                                    // The multiplication in the next line is necessary
                                    // because when slicing multiples of 32 bytes (lengthmod == 0)
                                    // the following copy loop was copying the origin's length
                                    // and then ending prematurely not copying everything it should.
                                    let mc := add(add(tempBytes, lengthmod), mul(0x20, iszero(lengthmod)))
                                    let end := add(mc, _length)
                                    for {
                                        // The multiplication in the next line has the same exact purpose
                                        // as the one above.
                                        let cc := add(add(add(_bytes, lengthmod), mul(0x20, iszero(lengthmod))), _start)
                                    } lt(mc, end) {
                                        mc := add(mc, 0x20)
                                        cc := add(cc, 0x20)
                                    } {
                                        mstore(mc, mload(cc))
                                    }
                                    mstore(tempBytes, _length)
                                    //update free-memory pointer
                                    //allocating the array padded to 32 bytes like the compiler does now
                                    mstore(0x40, and(add(mc, 31), not(31)))
                                }
                                //if we want a zero-length slice let's just return a zero-length array
                                default {
                                    tempBytes := mload(0x40)
                                    //zero out the 32 bytes slice we are about to return
                                    //we need to do it because Solidity does not garbage collect
                                    mstore(tempBytes, 0)
                                    mstore(0x40, add(tempBytes, 0x20))
                                }
                            }
                            return tempBytes;
                        }
                        /// @notice Slices a byte array with a given starting index up to the end of the original byte
                        ///         array. Returns a new array rathern than a pointer to the original.
                        /// @param _bytes Byte array to slice.
                        /// @param _start Starting index of the slice.
                        /// @return Slice of the input byte array.
                        function slice(bytes memory _bytes, uint256 _start) internal pure returns (bytes memory) {
                            if (_start >= _bytes.length) {
                                return bytes("");
                            }
                            return slice(_bytes, _start, _bytes.length - _start);
                        }
                        /// @notice Converts a byte array into a nibble array by splitting each byte into two nibbles.
                        ///         Resulting nibble array will be exactly twice as long as the input byte array.
                        /// @param _bytes Input byte array to convert.
                        /// @return Resulting nibble array.
                        function toNibbles(bytes memory _bytes) internal pure returns (bytes memory) {
                            bytes memory _nibbles;
                            assembly {
                                // Grab a free memory offset for the new array
                                _nibbles := mload(0x40)
                                // Load the length of the passed bytes array from memory
                                let bytesLength := mload(_bytes)
                                // Calculate the length of the new nibble array
                                // This is the length of the input array times 2
                                let nibblesLength := shl(0x01, bytesLength)
                                // Update the free memory pointer to allocate memory for the new array.
                                // To do this, we add the length of the new array + 32 bytes for the array length
                                // rounded up to the nearest 32 byte boundary to the current free memory pointer.
                                mstore(0x40, add(_nibbles, and(not(0x1F), add(nibblesLength, 0x3F))))
                                // Store the length of the new array in memory
                                mstore(_nibbles, nibblesLength)
                                // Store the memory offset of the _bytes array's contents on the stack
                                let bytesStart := add(_bytes, 0x20)
                                // Store the memory offset of the nibbles array's contents on the stack
                                let nibblesStart := add(_nibbles, 0x20)
                                // Loop through each byte in the input array
                                for {
                                    let i := 0x00
                                } lt(i, bytesLength) {
                                    i := add(i, 0x01)
                                } {
                                    // Get the starting offset of the next 2 bytes in the nibbles array
                                    let offset := add(nibblesStart, shl(0x01, i))
                                    // Load the byte at the current index within the `_bytes` array
                                    let b := byte(0x00, mload(add(bytesStart, i)))
                                    // Pull out the first nibble and store it in the new array
                                    mstore8(offset, shr(0x04, b))
                                    // Pull out the second nibble and store it in the new array
                                    mstore8(add(offset, 0x01), and(b, 0x0F))
                                }
                            }
                            return _nibbles;
                        }
                        /// @notice Compares two byte arrays by comparing their keccak256 hashes.
                        /// @param _bytes First byte array to compare.
                        /// @param _other Second byte array to compare.
                        /// @return True if the two byte arrays are equal, false otherwise.
                        function equal(bytes memory _bytes, bytes memory _other) internal pure returns (bool) {
                            return keccak256(_bytes) == keccak256(_other);
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    pragma solidity ^0.8.8;
                    /**
                     * @custom:attribution https://github.com/hamdiallam/Solidity-RLP
                     * @title RLPReader
                     * @notice RLPReader is a library for parsing RLP-encoded byte arrays into Solidity types. Adapted
                     *         from Solidity-RLP (https://github.com/hamdiallam/Solidity-RLP) by Hamdi Allam with
                     *         various tweaks to improve readability.
                     */
                    library RLPReader {
                        /**
                         * Custom pointer type to avoid confusion between pointers and uint256s.
                         */
                        type MemoryPointer is uint256;
                        /**
                         * @notice RLP item types.
                         *
                         * @custom:value DATA_ITEM Represents an RLP data item (NOT a list).
                         * @custom:value LIST_ITEM Represents an RLP list item.
                         */
                        enum RLPItemType {
                            DATA_ITEM,
                            LIST_ITEM
                        }
                        /**
                         * @notice Struct representing an RLP item.
                         *
                         * @custom:field length Length of the RLP item.
                         * @custom:field ptr    Pointer to the RLP item in memory.
                         */
                        struct RLPItem {
                            uint256 length;
                            MemoryPointer ptr;
                        }
                        /**
                         * @notice Max list length that this library will accept.
                         */
                        uint256 internal constant MAX_LIST_LENGTH = 32;
                        /**
                         * @notice Converts bytes to a reference to memory position and length.
                         *
                         * @param _in Input bytes to convert.
                         *
                         * @return Output memory reference.
                         */
                        function toRLPItem(bytes memory _in) internal pure returns (RLPItem memory) {
                            // Empty arrays are not RLP items.
                            require(
                                _in.length > 0,
                                "RLPReader: length of an RLP item must be greater than zero to be decodable"
                            );
                            MemoryPointer ptr;
                            assembly {
                                ptr := add(_in, 32)
                            }
                            return RLPItem({ length: _in.length, ptr: ptr });
                        }
                        /**
                         * @notice Reads an RLP list value into a list of RLP items.
                         *
                         * @param _in RLP list value.
                         *
                         * @return Decoded RLP list items.
                         */
                        function readList(RLPItem memory _in) internal pure returns (RLPItem[] memory) {
                            (uint256 listOffset, uint256 listLength, RLPItemType itemType) = _decodeLength(_in);
                            require(
                                itemType == RLPItemType.LIST_ITEM,
                                "RLPReader: decoded item type for list is not a list item"
                            );
                            require(
                                listOffset + listLength == _in.length,
                                "RLPReader: list item has an invalid data remainder"
                            );
                            // Solidity in-memory arrays can't be increased in size, but *can* be decreased in size by
                            // writing to the length. Since we can't know the number of RLP items without looping over
                            // the entire input, we'd have to loop twice to accurately size this array. It's easier to
                            // simply set a reasonable maximum list length and decrease the size before we finish.
                            RLPItem[] memory out = new RLPItem[](MAX_LIST_LENGTH);
                            uint256 itemCount = 0;
                            uint256 offset = listOffset;
                            while (offset < _in.length) {
                                (uint256 itemOffset, uint256 itemLength, ) = _decodeLength(
                                    RLPItem({
                                        length: _in.length - offset,
                                        ptr: MemoryPointer.wrap(MemoryPointer.unwrap(_in.ptr) + offset)
                                    })
                                );
                                // We don't need to check itemCount < out.length explicitly because Solidity already
                                // handles this check on our behalf, we'd just be wasting gas.
                                out[itemCount] = RLPItem({
                                    length: itemLength + itemOffset,
                                    ptr: MemoryPointer.wrap(MemoryPointer.unwrap(_in.ptr) + offset)
                                });
                                itemCount += 1;
                                offset += itemOffset + itemLength;
                            }
                            // Decrease the array size to match the actual item count.
                            assembly {
                                mstore(out, itemCount)
                            }
                            return out;
                        }
                        /**
                         * @notice Reads an RLP list value into a list of RLP items.
                         *
                         * @param _in RLP list value.
                         *
                         * @return Decoded RLP list items.
                         */
                        function readList(bytes memory _in) internal pure returns (RLPItem[] memory) {
                            return readList(toRLPItem(_in));
                        }
                        /**
                         * @notice Reads an RLP bytes value into bytes.
                         *
                         * @param _in RLP bytes value.
                         *
                         * @return Decoded bytes.
                         */
                        function readBytes(RLPItem memory _in) internal pure returns (bytes memory) {
                            (uint256 itemOffset, uint256 itemLength, RLPItemType itemType) = _decodeLength(_in);
                            require(
                                itemType == RLPItemType.DATA_ITEM,
                                "RLPReader: decoded item type for bytes is not a data item"
                            );
                            require(
                                _in.length == itemOffset + itemLength,
                                "RLPReader: bytes value contains an invalid remainder"
                            );
                            return _copy(_in.ptr, itemOffset, itemLength);
                        }
                        /**
                         * @notice Reads an RLP bytes value into bytes.
                         *
                         * @param _in RLP bytes value.
                         *
                         * @return Decoded bytes.
                         */
                        function readBytes(bytes memory _in) internal pure returns (bytes memory) {
                            return readBytes(toRLPItem(_in));
                        }
                        /**
                         * @notice Reads the raw bytes of an RLP item.
                         *
                         * @param _in RLP item to read.
                         *
                         * @return Raw RLP bytes.
                         */
                        function readRawBytes(RLPItem memory _in) internal pure returns (bytes memory) {
                            return _copy(_in.ptr, 0, _in.length);
                        }
                        /**
                         * @notice Decodes the length of an RLP item.
                         *
                         * @param _in RLP item to decode.
                         *
                         * @return Offset of the encoded data.
                         * @return Length of the encoded data.
                         * @return RLP item type (LIST_ITEM or DATA_ITEM).
                         */
                        function _decodeLength(RLPItem memory _in)
                            private
                            pure
                            returns (
                                uint256,
                                uint256,
                                RLPItemType
                            )
                        {
                            // Short-circuit if there's nothing to decode, note that we perform this check when
                            // the user creates an RLP item via toRLPItem, but it's always possible for them to bypass
                            // that function and create an RLP item directly. So we need to check this anyway.
                            require(
                                _in.length > 0,
                                "RLPReader: length of an RLP item must be greater than zero to be decodable"
                            );
                            MemoryPointer ptr = _in.ptr;
                            uint256 prefix;
                            assembly {
                                prefix := byte(0, mload(ptr))
                            }
                            if (prefix <= 0x7f) {
                                // Single byte.
                                return (0, 1, RLPItemType.DATA_ITEM);
                            } else if (prefix <= 0xb7) {
                                // Short string.
                                // slither-disable-next-line variable-scope
                                uint256 strLen = prefix - 0x80;
                                require(
                                    _in.length > strLen,
                                    "RLPReader: length of content must be greater than string length (short string)"
                                );
                                bytes1 firstByteOfContent;
                                assembly {
                                    firstByteOfContent := and(mload(add(ptr, 1)), shl(248, 0xff))
                                }
                                require(
                                    strLen != 1 || firstByteOfContent >= 0x80,
                                    "RLPReader: invalid prefix, single byte < 0x80 are not prefixed (short string)"
                                );
                                return (1, strLen, RLPItemType.DATA_ITEM);
                            } else if (prefix <= 0xbf) {
                                // Long string.
                                uint256 lenOfStrLen = prefix - 0xb7;
                                require(
                                    _in.length > lenOfStrLen,
                                    "RLPReader: length of content must be > than length of string length (long string)"
                                );
                                bytes1 firstByteOfContent;
                                assembly {
                                    firstByteOfContent := and(mload(add(ptr, 1)), shl(248, 0xff))
                                }
                                require(
                                    firstByteOfContent != 0x00,
                                    "RLPReader: length of content must not have any leading zeros (long string)"
                                );
                                uint256 strLen;
                                assembly {
                                    strLen := shr(sub(256, mul(8, lenOfStrLen)), mload(add(ptr, 1)))
                                }
                                require(
                                    strLen > 55,
                                    "RLPReader: length of content must be greater than 55 bytes (long string)"
                                );
                                require(
                                    _in.length > lenOfStrLen + strLen,
                                    "RLPReader: length of content must be greater than total length (long string)"
                                );
                                return (1 + lenOfStrLen, strLen, RLPItemType.DATA_ITEM);
                            } else if (prefix <= 0xf7) {
                                // Short list.
                                // slither-disable-next-line variable-scope
                                uint256 listLen = prefix - 0xc0;
                                require(
                                    _in.length > listLen,
                                    "RLPReader: length of content must be greater than list length (short list)"
                                );
                                return (1, listLen, RLPItemType.LIST_ITEM);
                            } else {
                                // Long list.
                                uint256 lenOfListLen = prefix - 0xf7;
                                require(
                                    _in.length > lenOfListLen,
                                    "RLPReader: length of content must be > than length of list length (long list)"
                                );
                                bytes1 firstByteOfContent;
                                assembly {
                                    firstByteOfContent := and(mload(add(ptr, 1)), shl(248, 0xff))
                                }
                                require(
                                    firstByteOfContent != 0x00,
                                    "RLPReader: length of content must not have any leading zeros (long list)"
                                );
                                uint256 listLen;
                                assembly {
                                    listLen := shr(sub(256, mul(8, lenOfListLen)), mload(add(ptr, 1)))
                                }
                                require(
                                    listLen > 55,
                                    "RLPReader: length of content must be greater than 55 bytes (long list)"
                                );
                                require(
                                    _in.length > lenOfListLen + listLen,
                                    "RLPReader: length of content must be greater than total length (long list)"
                                );
                                return (1 + lenOfListLen, listLen, RLPItemType.LIST_ITEM);
                            }
                        }
                        /**
                         * @notice Copies the bytes from a memory location.
                         *
                         * @param _src    Pointer to the location to read from.
                         * @param _offset Offset to start reading from.
                         * @param _length Number of bytes to read.
                         *
                         * @return Copied bytes.
                         */
                        function _copy(
                            MemoryPointer _src,
                            uint256 _offset,
                            uint256 _length
                        ) private pure returns (bytes memory) {
                            bytes memory out = new bytes(_length);
                            if (_length == 0) {
                                return out;
                            }
                            // Mostly based on Solidity's copy_memory_to_memory:
                            // solhint-disable max-line-length
                            // https://github.com/ethereum/solidity/blob/34dd30d71b4da730488be72ff6af7083cf2a91f6/libsolidity/codegen/YulUtilFunctions.cpp#L102-L114
                            uint256 src = MemoryPointer.unwrap(_src) + _offset;
                            assembly {
                                let dest := add(out, 32)
                                let i := 0
                                for {
                                } lt(i, _length) {
                                    i := add(i, 32)
                                } {
                                    mstore(add(dest, i), mload(add(src, i)))
                                }
                                if gt(i, _length) {
                                    mstore(add(dest, _length), 0)
                                }
                            }
                            return out;
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    // OpenZeppelin Contracts (last updated v4.5.0) (utils/math/SignedMath.sol)
                    pragma solidity ^0.8.0;
                    /**
                     * @dev Standard signed math utilities missing in the Solidity language.
                     */
                    library SignedMath {
                        /**
                         * @dev Returns the largest of two signed numbers.
                         */
                        function max(int256 a, int256 b) internal pure returns (int256) {
                            return a >= b ? a : b;
                        }
                        /**
                         * @dev Returns the smallest of two signed numbers.
                         */
                        function min(int256 a, int256 b) internal pure returns (int256) {
                            return a < b ? a : b;
                        }
                        /**
                         * @dev Returns the average of two signed numbers without overflow.
                         * The result is rounded towards zero.
                         */
                        function average(int256 a, int256 b) internal pure returns (int256) {
                            // Formula from the book "Hacker's Delight"
                            int256 x = (a & b) + ((a ^ b) >> 1);
                            return x + (int256(uint256(x) >> 255) & (a ^ b));
                        }
                        /**
                         * @dev Returns the absolute unsigned value of a signed value.
                         */
                        function abs(int256 n) internal pure returns (uint256) {
                            unchecked {
                                // must be unchecked in order to support `n = type(int256).min`
                                return uint256(n >= 0 ? n : -n);
                            }
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    pragma solidity >=0.8.0;
                    /// @notice Arithmetic library with operations for fixed-point numbers.
                    /// @author Solmate (https://github.com/Rari-Capital/solmate/blob/main/src/utils/FixedPointMathLib.sol)
                    library FixedPointMathLib {
                        /*//////////////////////////////////////////////////////////////
                                        SIMPLIFIED FIXED POINT OPERATIONS
                        //////////////////////////////////////////////////////////////*/
                        uint256 internal constant WAD = 1e18; // The scalar of ETH and most ERC20s.
                        function mulWadDown(uint256 x, uint256 y) internal pure returns (uint256) {
                            return mulDivDown(x, y, WAD); // Equivalent to (x * y) / WAD rounded down.
                        }
                        function mulWadUp(uint256 x, uint256 y) internal pure returns (uint256) {
                            return mulDivUp(x, y, WAD); // Equivalent to (x * y) / WAD rounded up.
                        }
                        function divWadDown(uint256 x, uint256 y) internal pure returns (uint256) {
                            return mulDivDown(x, WAD, y); // Equivalent to (x * WAD) / y rounded down.
                        }
                        function divWadUp(uint256 x, uint256 y) internal pure returns (uint256) {
                            return mulDivUp(x, WAD, y); // Equivalent to (x * WAD) / y rounded up.
                        }
                        function powWad(int256 x, int256 y) internal pure returns (int256) {
                            // Equivalent to x to the power of y because x ** y = (e ** ln(x)) ** y = e ** (ln(x) * y)
                            return expWad((lnWad(x) * y) / int256(WAD)); // Using ln(x) means x must be greater than 0.
                        }
                        function expWad(int256 x) internal pure returns (int256 r) {
                            unchecked {
                                // When the result is < 0.5 we return zero. This happens when
                                // x <= floor(log(0.5e18) * 1e18) ~ -42e18
                                if (x <= -42139678854452767551) return 0;
                                // When the result is > (2**255 - 1) / 1e18 we can not represent it as an
                                // int. This happens when x >= floor(log((2**255 - 1) / 1e18) * 1e18) ~ 135.
                                if (x >= 135305999368893231589) revert("EXP_OVERFLOW");
                                // x is now in the range (-42, 136) * 1e18. Convert to (-42, 136) * 2**96
                                // for more intermediate precision and a binary basis. This base conversion
                                // is a multiplication by 1e18 / 2**96 = 5**18 / 2**78.
                                x = (x << 78) / 5**18;
                                // Reduce range of x to (-½ ln 2, ½ ln 2) * 2**96 by factoring out powers
                                // of two such that exp(x) = exp(x') * 2**k, where k is an integer.
                                // Solving this gives k = round(x / log(2)) and x' = x - k * log(2).
                                int256 k = ((x << 96) / 54916777467707473351141471128 + 2**95) >> 96;
                                x = x - k * 54916777467707473351141471128;
                                // k is in the range [-61, 195].
                                // Evaluate using a (6, 7)-term rational approximation.
                                // p is made monic, we'll multiply by a scale factor later.
                                int256 y = x + 1346386616545796478920950773328;
                                y = ((y * x) >> 96) + 57155421227552351082224309758442;
                                int256 p = y + x - 94201549194550492254356042504812;
                                p = ((p * y) >> 96) + 28719021644029726153956944680412240;
                                p = p * x + (4385272521454847904659076985693276 << 96);
                                // We leave p in 2**192 basis so we don't need to scale it back up for the division.
                                int256 q = x - 2855989394907223263936484059900;
                                q = ((q * x) >> 96) + 50020603652535783019961831881945;
                                q = ((q * x) >> 96) - 533845033583426703283633433725380;
                                q = ((q * x) >> 96) + 3604857256930695427073651918091429;
                                q = ((q * x) >> 96) - 14423608567350463180887372962807573;
                                q = ((q * x) >> 96) + 26449188498355588339934803723976023;
                                assembly {
                                    // Div in assembly because solidity adds a zero check despite the unchecked.
                                    // The q polynomial won't have zeros in the domain as all its roots are complex.
                                    // No scaling is necessary because p is already 2**96 too large.
                                    r := sdiv(p, q)
                                }
                                // r should be in the range (0.09, 0.25) * 2**96.
                                // We now need to multiply r by:
                                // * the scale factor s = ~6.031367120.
                                // * the 2**k factor from the range reduction.
                                // * the 1e18 / 2**96 factor for base conversion.
                                // We do this all at once, with an intermediate result in 2**213
                                // basis, so the final right shift is always by a positive amount.
                                r = int256((uint256(r) * 3822833074963236453042738258902158003155416615667) >> uint256(195 - k));
                            }
                        }
                        function lnWad(int256 x) internal pure returns (int256 r) {
                            unchecked {
                                require(x > 0, "UNDEFINED");
                                // We want to convert x from 10**18 fixed point to 2**96 fixed point.
                                // We do this by multiplying by 2**96 / 10**18. But since
                                // ln(x * C) = ln(x) + ln(C), we can simply do nothing here
                                // and add ln(2**96 / 10**18) at the end.
                                // Reduce range of x to (1, 2) * 2**96
                                // ln(2^k * x) = k * ln(2) + ln(x)
                                int256 k = int256(log2(uint256(x))) - 96;
                                x <<= uint256(159 - k);
                                x = int256(uint256(x) >> 159);
                                // Evaluate using a (8, 8)-term rational approximation.
                                // p is made monic, we will multiply by a scale factor later.
                                int256 p = x + 3273285459638523848632254066296;
                                p = ((p * x) >> 96) + 24828157081833163892658089445524;
                                p = ((p * x) >> 96) + 43456485725739037958740375743393;
                                p = ((p * x) >> 96) - 11111509109440967052023855526967;
                                p = ((p * x) >> 96) - 45023709667254063763336534515857;
                                p = ((p * x) >> 96) - 14706773417378608786704636184526;
                                p = p * x - (795164235651350426258249787498 << 96);
                                // We leave p in 2**192 basis so we don't need to scale it back up for the division.
                                // q is monic by convention.
                                int256 q = x + 5573035233440673466300451813936;
                                q = ((q * x) >> 96) + 71694874799317883764090561454958;
                                q = ((q * x) >> 96) + 283447036172924575727196451306956;
                                q = ((q * x) >> 96) + 401686690394027663651624208769553;
                                q = ((q * x) >> 96) + 204048457590392012362485061816622;
                                q = ((q * x) >> 96) + 31853899698501571402653359427138;
                                q = ((q * x) >> 96) + 909429971244387300277376558375;
                                assembly {
                                    // Div in assembly because solidity adds a zero check despite the unchecked.
                                    // The q polynomial is known not to have zeros in the domain.
                                    // No scaling required because p is already 2**96 too large.
                                    r := sdiv(p, q)
                                }
                                // r is in the range (0, 0.125) * 2**96
                                // Finalization, we need to:
                                // * multiply by the scale factor s = 5.549…
                                // * add ln(2**96 / 10**18)
                                // * add k * ln(2)
                                // * multiply by 10**18 / 2**96 = 5**18 >> 78
                                // mul s * 5e18 * 2**96, base is now 5**18 * 2**192
                                r *= 1677202110996718588342820967067443963516166;
                                // add ln(2) * k * 5e18 * 2**192
                                r += 16597577552685614221487285958193947469193820559219878177908093499208371 * k;
                                // add ln(2**96 / 10**18) * 5e18 * 2**192
                                r += 600920179829731861736702779321621459595472258049074101567377883020018308;
                                // base conversion: mul 2**18 / 2**192
                                r >>= 174;
                            }
                        }
                        /*//////////////////////////////////////////////////////////////
                                        LOW LEVEL FIXED POINT OPERATIONS
                        //////////////////////////////////////////////////////////////*/
                        function mulDivDown(
                            uint256 x,
                            uint256 y,
                            uint256 denominator
                        ) internal pure returns (uint256 z) {
                            assembly {
                                // Store x * y in z for now.
                                z := mul(x, y)
                                // Equivalent to require(denominator != 0 && (x == 0 || (x * y) / x == y))
                                if iszero(and(iszero(iszero(denominator)), or(iszero(x), eq(div(z, x), y)))) {
                                    revert(0, 0)
                                }
                                // Divide z by the denominator.
                                z := div(z, denominator)
                            }
                        }
                        function mulDivUp(
                            uint256 x,
                            uint256 y,
                            uint256 denominator
                        ) internal pure returns (uint256 z) {
                            assembly {
                                // Store x * y in z for now.
                                z := mul(x, y)
                                // Equivalent to require(denominator != 0 && (x == 0 || (x * y) / x == y))
                                if iszero(and(iszero(iszero(denominator)), or(iszero(x), eq(div(z, x), y)))) {
                                    revert(0, 0)
                                }
                                // First, divide z - 1 by the denominator and add 1.
                                // We allow z - 1 to underflow if z is 0, because we multiply the
                                // end result by 0 if z is zero, ensuring we return 0 if z is zero.
                                z := mul(iszero(iszero(z)), add(div(sub(z, 1), denominator), 1))
                            }
                        }
                        function rpow(
                            uint256 x,
                            uint256 n,
                            uint256 scalar
                        ) internal pure returns (uint256 z) {
                            assembly {
                                switch x
                                case 0 {
                                    switch n
                                    case 0 {
                                        // 0 ** 0 = 1
                                        z := scalar
                                    }
                                    default {
                                        // 0 ** n = 0
                                        z := 0
                                    }
                                }
                                default {
                                    switch mod(n, 2)
                                    case 0 {
                                        // If n is even, store scalar in z for now.
                                        z := scalar
                                    }
                                    default {
                                        // If n is odd, store x in z for now.
                                        z := x
                                    }
                                    // Shifting right by 1 is like dividing by 2.
                                    let half := shr(1, scalar)
                                    for {
                                        // Shift n right by 1 before looping to halve it.
                                        n := shr(1, n)
                                    } n {
                                        // Shift n right by 1 each iteration to halve it.
                                        n := shr(1, n)
                                    } {
                                        // Revert immediately if x ** 2 would overflow.
                                        // Equivalent to iszero(eq(div(xx, x), x)) here.
                                        if shr(128, x) {
                                            revert(0, 0)
                                        }
                                        // Store x squared.
                                        let xx := mul(x, x)
                                        // Round to the nearest number.
                                        let xxRound := add(xx, half)
                                        // Revert if xx + half overflowed.
                                        if lt(xxRound, xx) {
                                            revert(0, 0)
                                        }
                                        // Set x to scaled xxRound.
                                        x := div(xxRound, scalar)
                                        // If n is even:
                                        if mod(n, 2) {
                                            // Compute z * x.
                                            let zx := mul(z, x)
                                            // If z * x overflowed:
                                            if iszero(eq(div(zx, x), z)) {
                                                // Revert if x is non-zero.
                                                if iszero(iszero(x)) {
                                                    revert(0, 0)
                                                }
                                            }
                                            // Round to the nearest number.
                                            let zxRound := add(zx, half)
                                            // Revert if zx + half overflowed.
                                            if lt(zxRound, zx) {
                                                revert(0, 0)
                                            }
                                            // Return properly scaled zxRound.
                                            z := div(zxRound, scalar)
                                        }
                                    }
                                }
                            }
                        }
                        /*//////////////////////////////////////////////////////////////
                                            GENERAL NUMBER UTILITIES
                        //////////////////////////////////////////////////////////////*/
                        function sqrt(uint256 x) internal pure returns (uint256 z) {
                            assembly {
                                let y := x // We start y at x, which will help us make our initial estimate.
                                z := 181 // The "correct" value is 1, but this saves a multiplication later.
                                // This segment is to get a reasonable initial estimate for the Babylonian method. With a bad
                                // start, the correct # of bits increases ~linearly each iteration instead of ~quadratically.
                                // We check y >= 2^(k + 8) but shift right by k bits
                                // each branch to ensure that if x >= 256, then y >= 256.
                                if iszero(lt(y, 0x10000000000000000000000000000000000)) {
                                    y := shr(128, y)
                                    z := shl(64, z)
                                }
                                if iszero(lt(y, 0x1000000000000000000)) {
                                    y := shr(64, y)
                                    z := shl(32, z)
                                }
                                if iszero(lt(y, 0x10000000000)) {
                                    y := shr(32, y)
                                    z := shl(16, z)
                                }
                                if iszero(lt(y, 0x1000000)) {
                                    y := shr(16, y)
                                    z := shl(8, z)
                                }
                                // Goal was to get z*z*y within a small factor of x. More iterations could
                                // get y in a tighter range. Currently, we will have y in [256, 256*2^16).
                                // We ensured y >= 256 so that the relative difference between y and y+1 is small.
                                // That's not possible if x < 256 but we can just verify those cases exhaustively.
                                // Now, z*z*y <= x < z*z*(y+1), and y <= 2^(16+8), and either y >= 256, or x < 256.
                                // Correctness can be checked exhaustively for x < 256, so we assume y >= 256.
                                // Then z*sqrt(y) is within sqrt(257)/sqrt(256) of sqrt(x), or about 20bps.
                                // For s in the range [1/256, 256], the estimate f(s) = (181/1024) * (s+1) is in the range
                                // (1/2.84 * sqrt(s), 2.84 * sqrt(s)), with largest error when s = 1 and when s = 256 or 1/256.
                                // Since y is in [256, 256*2^16), let a = y/65536, so that a is in [1/256, 256). Then we can estimate
                                // sqrt(y) using sqrt(65536) * 181/1024 * (a + 1) = 181/4 * (y + 65536)/65536 = 181 * (y + 65536)/2^18.
                                // There is no overflow risk here since y < 2^136 after the first branch above.
                                z := shr(18, mul(z, add(y, 65536))) // A mul() is saved from starting z at 181.
                                // Given the worst case multiplicative error of 2.84 above, 7 iterations should be enough.
                                z := shr(1, add(z, div(x, z)))
                                z := shr(1, add(z, div(x, z)))
                                z := shr(1, add(z, div(x, z)))
                                z := shr(1, add(z, div(x, z)))
                                z := shr(1, add(z, div(x, z)))
                                z := shr(1, add(z, div(x, z)))
                                z := shr(1, add(z, div(x, z)))
                                // If x+1 is a perfect square, the Babylonian method cycles between
                                // floor(sqrt(x)) and ceil(sqrt(x)). This statement ensures we return floor.
                                // See: https://en.wikipedia.org/wiki/Integer_square_root#Using_only_integer_division
                                // Since the ceil is rare, we save gas on the assignment and repeat division in the rare case.
                                // If you don't care whether the floor or ceil square root is returned, you can remove this statement.
                                z := sub(z, lt(div(x, z), z))
                            }
                        }
                        function log2(uint256 x) internal pure returns (uint256 r) {
                            require(x > 0, "UNDEFINED");
                            assembly {
                                r := shl(7, lt(0xffffffffffffffffffffffffffffffff, x))
                                r := or(r, shl(6, lt(0xffffffffffffffff, shr(r, x))))
                                r := or(r, shl(5, lt(0xffffffff, shr(r, x))))
                                r := or(r, shl(4, lt(0xffff, shr(r, x))))
                                r := or(r, shl(3, lt(0xff, shr(r, x))))
                                r := or(r, shl(2, lt(0xf, shr(r, x))))
                                r := or(r, shl(1, lt(0x3, shr(r, x))))
                                r := or(r, lt(0x1, shr(r, x)))
                            }
                        }
                    }
                    // SPDX-License-Identifier: MIT
                    // OpenZeppelin Contracts (last updated v4.7.0) (utils/Address.sol)
                    pragma solidity ^0.8.1;
                    /**
                     * @dev Collection of functions related to the address type
                     */
                    library AddressUpgradeable {
                        /**
                         * @dev Returns true if `account` is a contract.
                         *
                         * [IMPORTANT]
                         * ====
                         * It is unsafe to assume that an address for which this function returns
                         * false is an externally-owned account (EOA) and not a contract.
                         *
                         * Among others, `isContract` will return false for the following
                         * types of addresses:
                         *
                         *  - an externally-owned account
                         *  - a contract in construction
                         *  - an address where a contract will be created
                         *  - an address where a contract lived, but was destroyed
                         * ====
                         *
                         * [IMPORTANT]
                         * ====
                         * You shouldn't rely on `isContract` to protect against flash loan attacks!
                         *
                         * Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets
                         * like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract
                         * constructor.
                         * ====
                         */
                        function isContract(address account) internal view returns (bool) {
                            // This method relies on extcodesize/address.code.length, which returns 0
                            // for contracts in construction, since the code is only stored at the end
                            // of the constructor execution.
                            return account.code.length > 0;
                        }
                        /**
                         * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
                         * `recipient`, forwarding all available gas and reverting on errors.
                         *
                         * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
                         * of certain opcodes, possibly making contracts go over the 2300 gas limit
                         * imposed by `transfer`, making them unable to receive funds via
                         * `transfer`. {sendValue} removes this limitation.
                         *
                         * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
                         *
                         * IMPORTANT: because control is transferred to `recipient`, care must be
                         * taken to not create reentrancy vulnerabilities. Consider using
                         * {ReentrancyGuard} or the
                         * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
                         */
                        function sendValue(address payable recipient, uint256 amount) internal {
                            require(address(this).balance >= amount, "Address: insufficient balance");
                            (bool success, ) = recipient.call{value: amount}("");
                            require(success, "Address: unable to send value, recipient may have reverted");
                        }
                        /**
                         * @dev Performs a Solidity function call using a low level `call`. A
                         * plain `call` is an unsafe replacement for a function call: use this
                         * function instead.
                         *
                         * If `target` reverts with a revert reason, it is bubbled up by this
                         * function (like regular Solidity function calls).
                         *
                         * Returns the raw returned data. To convert to the expected return value,
                         * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
                         *
                         * Requirements:
                         *
                         * - `target` must be a contract.
                         * - calling `target` with `data` must not revert.
                         *
                         * _Available since v3.1._
                         */
                        function functionCall(address target, bytes memory data) internal returns (bytes memory) {
                            return functionCall(target, data, "Address: low-level call failed");
                        }
                        /**
                         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
                         * `errorMessage` as a fallback revert reason when `target` reverts.
                         *
                         * _Available since v3.1._
                         */
                        function functionCall(
                            address target,
                            bytes memory data,
                            string memory errorMessage
                        ) internal returns (bytes memory) {
                            return functionCallWithValue(target, data, 0, errorMessage);
                        }
                        /**
                         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
                         * but also transferring `value` wei to `target`.
                         *
                         * Requirements:
                         *
                         * - the calling contract must have an ETH balance of at least `value`.
                         * - the called Solidity function must be `payable`.
                         *
                         * _Available since v3.1._
                         */
                        function functionCallWithValue(
                            address target,
                            bytes memory data,
                            uint256 value
                        ) internal returns (bytes memory) {
                            return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
                        }
                        /**
                         * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
                         * with `errorMessage` as a fallback revert reason when `target` reverts.
                         *
                         * _Available since v3.1._
                         */
                        function functionCallWithValue(
                            address target,
                            bytes memory data,
                            uint256 value,
                            string memory errorMessage
                        ) internal returns (bytes memory) {
                            require(address(this).balance >= value, "Address: insufficient balance for call");
                            require(isContract(target), "Address: call to non-contract");
                            (bool success, bytes memory returndata) = target.call{value: value}(data);
                            return verifyCallResult(success, returndata, errorMessage);
                        }
                        /**
                         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
                         * but performing a static call.
                         *
                         * _Available since v3.3._
                         */
                        function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
                            return functionStaticCall(target, data, "Address: low-level static call failed");
                        }
                        /**
                         * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
                         * but performing a static call.
                         *
                         * _Available since v3.3._
                         */
                        function functionStaticCall(
                            address target,
                            bytes memory data,
                            string memory errorMessage
                        ) internal view returns (bytes memory) {
                            require(isContract(target), "Address: static call to non-contract");
                            (bool success, bytes memory returndata) = target.staticcall(data);
                            return verifyCallResult(success, returndata, errorMessage);
                        }
                        /**
                         * @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the
                         * revert reason using the provided one.
                         *
                         * _Available since v4.3._
                         */
                        function verifyCallResult(
                            bool success,
                            bytes memory returndata,
                            string memory errorMessage
                        ) internal pure returns (bytes memory) {
                            if (success) {
                                return returndata;
                            } else {
                                // Look for revert reason and bubble it up if present
                                if (returndata.length > 0) {
                                    // The easiest way to bubble the revert reason is using memory via assembly
                                    /// @solidity memory-safe-assembly
                                    assembly {
                                        let returndata_size := mload(returndata)
                                        revert(add(32, returndata), returndata_size)
                                    }
                                } else {
                                    revert(errorMessage);
                                }
                            }
                        }
                    }
                    

                    File 11 of 11: Proxy
                    // SPDX-License-Identifier: MIT
                    pragma solidity 0.8.15;
                    /**
                     * @title Proxy
                     * @notice Proxy is a transparent proxy that passes through the call if the caller is the owner or
                     *         if the caller is address(0), meaning that the call originated from an off-chain
                     *         simulation.
                     */
                    contract Proxy {
                        /**
                         * @notice The storage slot that holds the address of the implementation.
                         *         bytes32(uint256(keccak256('eip1967.proxy.implementation')) - 1)
                         */
                        bytes32 internal constant IMPLEMENTATION_KEY =
                            0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;
                        /**
                         * @notice The storage slot that holds the address of the owner.
                         *         bytes32(uint256(keccak256('eip1967.proxy.admin')) - 1)
                         */
                        bytes32 internal constant OWNER_KEY =
                            0xb53127684a568b3173ae13b9f8a6016e243e63b6e8ee1178d6a717850b5d6103;
                        /**
                         * @notice An event that is emitted each time the implementation is changed. This event is part
                         *         of the EIP-1967 specification.
                         *
                         * @param implementation The address of the implementation contract
                         */
                        event Upgraded(address indexed implementation);
                        /**
                         * @notice An event that is emitted each time the owner is upgraded. This event is part of the
                         *         EIP-1967 specification.
                         *
                         * @param previousAdmin The previous owner of the contract
                         * @param newAdmin      The new owner of the contract
                         */
                        event AdminChanged(address previousAdmin, address newAdmin);
                        /**
                         * @notice A modifier that reverts if not called by the owner or by address(0) to allow
                         *         eth_call to interact with this proxy without needing to use low-level storage
                         *         inspection. We assume that nobody is able to trigger calls from address(0) during
                         *         normal EVM execution.
                         */
                        modifier proxyCallIfNotAdmin() {
                            if (msg.sender == _getAdmin() || msg.sender == address(0)) {
                                _;
                            } else {
                                // This WILL halt the call frame on completion.
                                _doProxyCall();
                            }
                        }
                        /**
                         * @notice Sets the initial admin during contract deployment. Admin address is stored at the
                         *         EIP-1967 admin storage slot so that accidental storage collision with the
                         *         implementation is not possible.
                         *
                         * @param _admin Address of the initial contract admin. Admin as the ability to access the
                         *               transparent proxy interface.
                         */
                        constructor(address _admin) {
                            _changeAdmin(_admin);
                        }
                        // slither-disable-next-line locked-ether
                        receive() external payable {
                            // Proxy call by default.
                            _doProxyCall();
                        }
                        // slither-disable-next-line locked-ether
                        fallback() external payable {
                            // Proxy call by default.
                            _doProxyCall();
                        }
                        /**
                         * @notice Set the implementation contract address. The code at the given address will execute
                         *         when this contract is called.
                         *
                         * @param _implementation Address of the implementation contract.
                         */
                        function upgradeTo(address _implementation) public virtual proxyCallIfNotAdmin {
                            _setImplementation(_implementation);
                        }
                        /**
                         * @notice Set the implementation and call a function in a single transaction. Useful to ensure
                         *         atomic execution of initialization-based upgrades.
                         *
                         * @param _implementation Address of the implementation contract.
                         * @param _data           Calldata to delegatecall the new implementation with.
                         */
                        function upgradeToAndCall(address _implementation, bytes calldata _data)
                            public
                            payable
                            virtual
                            proxyCallIfNotAdmin
                            returns (bytes memory)
                        {
                            _setImplementation(_implementation);
                            (bool success, bytes memory returndata) = _implementation.delegatecall(_data);
                            require(success, "Proxy: delegatecall to new implementation contract failed");
                            return returndata;
                        }
                        /**
                         * @notice Changes the owner of the proxy contract. Only callable by the owner.
                         *
                         * @param _admin New owner of the proxy contract.
                         */
                        function changeAdmin(address _admin) public virtual proxyCallIfNotAdmin {
                            _changeAdmin(_admin);
                        }
                        /**
                         * @notice Gets the owner of the proxy contract.
                         *
                         * @return Owner address.
                         */
                        function admin() public virtual proxyCallIfNotAdmin returns (address) {
                            return _getAdmin();
                        }
                        /**
                         * @notice Queries the implementation address.
                         *
                         * @return Implementation address.
                         */
                        function implementation() public virtual proxyCallIfNotAdmin returns (address) {
                            return _getImplementation();
                        }
                        /**
                         * @notice Sets the implementation address.
                         *
                         * @param _implementation New implementation address.
                         */
                        function _setImplementation(address _implementation) internal {
                            assembly {
                                sstore(IMPLEMENTATION_KEY, _implementation)
                            }
                            emit Upgraded(_implementation);
                        }
                        /**
                         * @notice Changes the owner of the proxy contract.
                         *
                         * @param _admin New owner of the proxy contract.
                         */
                        function _changeAdmin(address _admin) internal {
                            address previous = _getAdmin();
                            assembly {
                                sstore(OWNER_KEY, _admin)
                            }
                            emit AdminChanged(previous, _admin);
                        }
                        /**
                         * @notice Performs the proxy call via a delegatecall.
                         */
                        function _doProxyCall() internal {
                            address impl = _getImplementation();
                            require(impl != address(0), "Proxy: implementation not initialized");
                            assembly {
                                // Copy calldata into memory at 0x0....calldatasize.
                                calldatacopy(0x0, 0x0, calldatasize())
                                // Perform the delegatecall, make sure to pass all available gas.
                                let success := delegatecall(gas(), impl, 0x0, calldatasize(), 0x0, 0x0)
                                // Copy returndata into memory at 0x0....returndatasize. Note that this *will*
                                // overwrite the calldata that we just copied into memory but that doesn't really
                                // matter because we'll be returning in a second anyway.
                                returndatacopy(0x0, 0x0, returndatasize())
                                // Success == 0 means a revert. We'll revert too and pass the data up.
                                if iszero(success) {
                                    revert(0x0, returndatasize())
                                }
                                // Otherwise we'll just return and pass the data up.
                                return(0x0, returndatasize())
                            }
                        }
                        /**
                         * @notice Queries the implementation address.
                         *
                         * @return Implementation address.
                         */
                        function _getImplementation() internal view returns (address) {
                            address impl;
                            assembly {
                                impl := sload(IMPLEMENTATION_KEY)
                            }
                            return impl;
                        }
                        /**
                         * @notice Queries the owner of the proxy contract.
                         *
                         * @return Owner address.
                         */
                        function _getAdmin() internal view returns (address) {
                            address owner;
                            assembly {
                                owner := sload(OWNER_KEY)
                            }
                            return owner;
                        }
                    }