// File: contracts/ERC721Creator.sol




// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

/// @author: manifold.xyz

import "@openzeppelin/contracts/proxy/Proxy.sol";
import "@openzeppelin/contracts/utils/Address.sol";
import "@openzeppelin/contracts/utils/StorageSlot.sol";

contract ERC721Creator is Proxy {
    
    constructor(string memory name, string memory symbol) {
        assert(_IMPLEMENTATION_SLOT == bytes32(uint256(keccak256("eip1967.proxy.implementation")) - 1));
        StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value = 0xe4E4003afE3765Aca8149a82fc064C0b125B9e5a;
        Address.functionDelegateCall(
            0xe4E4003afE3765Aca8149a82fc064C0b125B9e5a,
            abi.encodeWithSignature("initialize(string,string)", name, symbol)
        );
    }
        
    /**
     * @dev Storage slot with the address of the current implementation.
     * This is the keccak-256 hash of "eip1967.proxy.implementation" subtracted by 1, and is
     * validated in the constructor.
     */
    bytes32 internal constant _IMPLEMENTATION_SLOT = 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;

    /**
     * @dev Returns the current implementation address.
     */
     function implementation() public view returns (address) {
        return _implementation();
    }

    function _implementation() internal override view returns (address) {
        return StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value;
    }    

}

// File: contracts/NFTTOA.sol




// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

/// @title: NFT-TODD-AO
/// @author: manifold.xyz

import "./ERC721Creator.sol";

///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//                                                                                                                                           //
//                                                                                                                                           //
//    /**                                                                                                                                    //
//     *Submitted for verification at Etherscan.io on 2020-10-14                                                                             //
//    */                                                                                                                                     //
//                                                                                                                                           //
//    // ┏━━━┓━┏┓━┏┓━━┏━━━┓━━┏━━━┓━━━━┏━━━┓━━━━━━━━━━━━━━━━━━━┏┓━━━━━┏━━━┓━━━━━━━━━┏┓━━━━━━━━━━━━━━┏┓━                                       //
//    // ┃┏━━┛┏┛┗┓┃┃━━┃┏━┓┃━━┃┏━┓┃━━━━┗┓┏┓┃━━━━━━━━━━━━━━━━━━┏┛┗┓━━━━┃┏━┓┃━━━━━━━━┏┛┗┓━━━━━━━━━━━━┏┛┗┓                                       //
//    // ┃┗━━┓┗┓┏┛┃┗━┓┗┛┏┛┃━━┃┃━┃┃━━━━━┃┃┃┃┏━━┓┏━━┓┏━━┓┏━━┓┏┓┗┓┏┛━━━━┃┃━┗┛┏━━┓┏━┓━┗┓┏┛┏━┓┏━━┓━┏━━┓┗┓┏┛                                       //
//    // ┃┏━━┛━┃┃━┃┏┓┃┏━┛┏┛━━┃┃━┃┃━━━━━┃┃┃┃┃┏┓┃┃┏┓┃┃┏┓┃┃━━┫┣┫━┃┃━━━━━┃┃━┏┓┃┏┓┃┃┏┓┓━┃┃━┃┏┛┗━┓┃━┃┏━┛━┃┃━                                       //
//    // ┃┗━━┓━┃┗┓┃┃┃┃┃┃┗━┓┏┓┃┗━┛┃━━━━┏┛┗┛┃┃┃━┫┃┗┛┃┃┗┛┃┣━━┃┃┃━┃┗┓━━━━┃┗━┛┃┃┗┛┃┃┃┃┃━┃┗┓┃┃━┃┗┛┗┓┃┗━┓━┃┗┓                                       //
//    // ┗━━━┛━┗━┛┗┛┗┛┗━━━┛┗┛┗━━━┛━━━━┗━━━┛┗━━┛┃┏━┛┗━━┛┗━━┛┗┛━┗━┛━━━━┗━━━┛┗━━┛┗┛┗┛━┗━┛┗┛━┗━━━┛┗━━┛━┗━┛                                       //
//    // ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┃┃━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━                                       //
//    // ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┗┛━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━                                       //
//                                                                                                                                           //
//    // TODD-AO License-Identifier: CC0-1.0                                                                                                 //
//                                                                                                                                           //
//    pragma solidity 0.6.11;                                                                                                                //
//                                                                                                                                           //
//    // This interface is designed to be compatible with the Vyper version.                                                                 //
//    /// @notice This is the Ethereum 2.0 deposit contract interface.                                                                       //
//    /// For more information see the Phase 0 specification under https://github.com/ethereum/eth2.0-specs                                  //
//    interface IDepositContract {                                                                                                           //
//        /// @notice A processed deposit event.                                                                                             //
//        event DepositEvent(                                                                                                                //
//            bytes pubkey,                                                                                                                  //
//            bytes withdrawal_credentials,                                                                                                  //
//            bytes amount,                                                                                                                  //
//            bytes signature,                                                                                                               //
//            bytes index                                                                                                                    //
//        );                                                                                                                                 //
//                                                                                                                                           //
//        /// @notice Submit a Phase 0 DepositData object.                                                                                   //
//        /// @param pubkey A BLS12-381 public key.                                                                                          //
//        /// @param withdrawal_credentials Commitment to a public key for withdrawals.                                                      //
//        /// @param signature A BLS12-381 signature.                                                                                        //
//        /// @param deposit_data_root The SHA-256 hash of the SSZ-encoded DepositData object.                                               //
//        /// Used as a protection against malformed input.                                                                                  //
//        function deposit(                                                                                                                  //
//            bytes calldata pubkey,                                                                                                         //
//            bytes calldata withdrawal_credentials,                                                                                         //
//            bytes calldata signature,                                                                                                      //
//            bytes32 deposit_data_root                                                                                                      //
//        ) external payable;                                                                                                                //
//                                                                                                                                           //
//        /// @notice Query the current deposit root hash.                                                                                   //
//        /// @return The deposit root hash.                                                                                                 //
//        function get_deposit_root() external view returns (bytes32);                                                                       //
//                                                                                                                                           //
//        /// @notice Query the current deposit count.                                                                                       //
//        /// @return The deposit count encoded as a little endian 64-bit number.                                                            //
//        function get_deposit_count() external view returns (bytes memory);                                                                 //
//    }                                                                                                                                      //
//                                                                                                                                           //
//    // Based on official specification in https://eips.ethereum.org/EIPS/eip-165                                                           //
//    interface ERC165 {                                                                                                                     //
//        /// @notice Query if a contract implements an interface                                                                            //
//        /// @param interfaceId The interface identifier, as specified in ERC-165                                                           //
//        /// @dev Interface identification is specified in ERC-165. This function                                                           //
//        ///  uses less than 30,000 gas.                                                                                                    //
//        /// @return `true` if the contract implements `interfaceId` and                                                                    //
//        ///  `interfaceId` is not 0xffffffff, `false` otherwise                                                                            //
//        function supportsInterface(bytes4 interfaceId) external pure returns (bool);                                                       //
//    }                                                                                                                                      //
//                                                                                                                                           //
//    // This is a rewrite of the Vyper Eth2.0 deposit contract in Solidity.                                                                 //
//    // It tries to stay as close as possible to the original source code.                                                                  //
//    /// @notice This is the Ethereum 2.0 deposit contract interface.                                                                       //
//    /// For more information see the Phase 0 specification under https://github.com/ethereum/eth2.0-specs                                  //
//    contract DepositContract is IDepositContract, ERC165 {                                                                                 //
//        uint constant DEPOSIT_CONTRACT_TREE_DEPTH = 32;                                                                                    //
//        // NOTE: this also ensures `deposit_count` will fit into 64-bits                                                                   //
//        uint constant MAX_DEPOSIT_COUNT = 2**DEPOSIT_CONTRACT_TREE_DEPTH - 1;                                                              //
//                                                                                                                                           //
//        bytes32[DEPOSIT_CONTRACT_TREE_DEPTH] branch;                                                                                       //
//        uint256 deposit_count;                                                                                                             //
//                                                                                                                                           //
//        bytes32[DEPOSIT_CONTRACT_TREE_DEPTH] zero_hashes;                                                                                  //
//                                                                                                                                           //
//        constructor() public {                                                                                                             //
//            // Compute hashes in empty sparse Merkle tree                                                                                  //
//            for (uint height = 0; height < DEPOSIT_CONTRACT_TREE_DEPTH - 1; height++)                                                      //
//                zero_hashes[height + 1] = sha256(abi.encodePacked(zero_hashes[height], zero_hashes[height]));                              //
//        }                                                                                                                                  //
//                                                                                                                                           //
//        function get_deposit_root() override external view returns (bytes32) {                                                             //
//            bytes32 node;                                                                                                                  //
//            uint size = deposit_count;                                                                                                     //
//            for (uint height = 0; height < DEPOSIT_CONTRACT_TREE_DEPTH; height++) {                                                        //
//                if ((size & 1) == 1)                                                                                                       //
//                    node = sha256(abi.encodePacked(branch[height], node));                                                                 //
//                else                                                                                                                       //
//                    node = sha256(abi.encodePacked(node, zero_hashes[height]));                                                            //
//                size /= 2;                                                                                                                 //
//            }                                                                                                                              //
//            return sha256(abi.encodePacked(                                                                                                //
//                node,                                                                                                                      //
//                to_little_endian_64(uint64(deposit_count)),                                                                                //
//                bytes24(0)                                                                                                                 //
//            ));                                                                                                                            //
//        }                                                                                                                                  //
//                                                                                                                                           //
//        function get_deposit_count() override external view returns (bytes memory) {                                                       //
//            return to_little_endian_64(uint64(deposit_count));                                                                             //
//        }                                                                                                                                  //
//                                                                                                                                           //
//        function deposit(                                                                                                                  //
//            bytes calldata pubkey,                                                                                                         //
//            bytes calldata withdrawal_credentials,                                                                                         //
//            bytes calldata signature,                                                                                                      //
//            bytes32 deposit_data_root                                                                                                      //
//        ) override external payable {                                                                                                      //
//            // Extended ABI length checks since dynamic types are used.                                                                    //
//            require(pubkey.length == 48, "DepositContract: invalid pubkey length");                                                        //
//            require(withdrawal_credentials.length == 32, "DepositContract: invalid withdrawal_credentials length");                        //
//            require(signature.length == 96, "DepositContract: invalid signature length");                                                  //
//                                                                                                                                           //
//            // Check deposit amount                                                                                                        //
//            require(msg.value >= 1 ether, "DepositContract: deposit value too low");                                                       //
//            require(msg.value % 1 gwei == 0, "DepositContract: deposit value not multiple of gwei");                                       //
//            uint deposit_amount = msg.value / 1 gwei;                                                                                      //
//            require(deposit_amount <= type(uint64).max, "DepositContract: deposit value too high");                                        //
//                                                                                                                                           //
//            // Emit `DepositEvent` log                                                                                                     //
//            bytes memory amount = to_little_endian_64(uint64(deposit_amount));                                                             //
//            emit DepositEvent(                                                                                                             //
//                pubkey,                                                                                                                    //
//                withdrawal_credentials,                                                                                                    //
//                amount,                                                                                                                    //
//                signature,                                                                                                                 //
//                to_little_endian_64(uint64(deposit_count))                                                                                 //
//            );                                                                                                                             //
//                                                                                                                                           //
//            // Compute deposit data root (`DepositData` hash tree root)                                                                    //
//            bytes32 pubkey_root = sha256(abi.encodePacked(pubkey, bytes16(0)));                                                            //
//            bytes32 signature_root = sha256(abi.encodePacked(                                                                              //
//                sha256(abi.encodePacked(signature[:64])),                                                                                  //
//                sha256(abi.encodePacked(signature[64:], bytes32(0)))                                                                       //
//            ));                                                                                                                            //
//            bytes32 node = sha256(abi.encodePacked(                                                                                        //
//                sha256(abi.encodePacked(pubkey_root, withdrawal_credentials)),                                                             //
//                sha256(abi.encodePacked(amount, bytes24(0), signature_root))                                                               //
//            ));                                                                                                                            //
//                                                                                                                                           //
//            // Verify computed and expected deposit data roots match                                                                       //
//            require(node == deposit_data_root, "DepositContract: reconstructed DepositData does not match supplied deposit_data_root");    //
//                                                                                                                                           //
//            // Avoid overflowing the Merkle tree (and prevent edge case in computing `branch`)                                             //
//            require(deposit_count < MAX_DEPOSIT_COUNT, "DepositContract: merkle tree full");                                               //
//                                                                                                                                           //
//            // Add deposit data root to Merkle tree (update a single `branch` node)                                                        //
//            deposit_count += 1;                                                                                                            //
//            uint size = deposit_count;                                                                                                     //
//            for (uint height = 0; height < DEPOSIT_CONTRACT_TREE_DEPTH; height++) {                                                        //
//                if ((size & 1) == 1) {                                                                                                     //
//                    branch[height] = node;                                                                                                 //
//                    return;                                                                                                                //
//                }                                                                                                                          //
//                node = sha256(abi.encodePacked(branch[height], node));                                                                     //
//                size /= 2;                                                                                                                 //
//            }                                                                                                                              //
//            // As the loop should always end prematurely with the `return` statement,                                                      //
//            // this code should be unreachable. We assert `false` just to be safe.                                                         //
//            assert(false);                                                                                                                 //
//        }                                                                                                                                  //
//                                                                                                                                           //
//        function supportsInterface(bytes4 interfaceId) override external pure returns (bool) {                                             //
//            return interfaceId == type(ERC165).interfaceId || interfaceId == type(IDepositContract).interfaceId;                           //
//        }                                                                                                                                  //
//                                                                                                                                           //
//        function to_little_endian_64(uint64 value) internal pure returns (bytes memory ret) {                                              //
//            ret = new bytes(8);                                                                                                            //
//            bytes8 bytesValue = bytes8(value);                                                                                             //
//            // Byteswapping during copying to bytes.                                                                                       //
//            ret[0] = bytesValue[7];                                                                                                        //
//            ret[1] = bytesValue[6];                                                                                                        //
//            ret[2] = bytesValue[5];                                                                                                        //
//            ret[3] = bytesValue[4];                                                                                                        //
//            ret[4] = bytesValue[3];                                                                                                        //
//            ret[5] = bytesValue[2];                                                                                                        //
//            ret[6] = bytesValue[1];                                                                                                        //
//            ret[7] = bytesValue[0];                                                                                                        //
//        }                                                                                                                                  //
//    }                                                                                                                                      //
//                                                                                                                                           //
//                                                                                                                                           //
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////


contract NFTTOA is ERC721Creator {
    constructor() ERC721Creator("NFT-TODD-AO", "NFTTOA") {}
}

// File: node_modules/@openzeppelin/contracts/proxy/Proxy.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.6.0) (proxy/Proxy.sol)

pragma solidity ^0.8.0;

/**
 * @dev This abstract contract provides a fallback function that delegates all calls to another contract using the EVM
 * instruction `delegatecall`. We refer to the second contract as the _implementation_ behind the proxy, and it has to
 * be specified by overriding the virtual {_implementation} function.
 *
 * Additionally, delegation to the implementation can be triggered manually through the {_fallback} function, or to a
 * different contract through the {_delegate} function.
 *
 * The success and return data of the delegated call will be returned back to the caller of the proxy.
 */
abstract contract Proxy {
    /**
     * @dev Delegates the current call to `implementation`.
     *
     * This function does not return to its internal call site, it will return directly to the external caller.
     */
    function _delegate(address implementation) internal virtual {
        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 This is a virtual function that should be overridden so it returns the address to which the fallback function
     * and {_fallback} should delegate.
     */
    function _implementation() internal view virtual returns (address);

    /**
     * @dev Delegates the current call to the address returned by `_implementation()`.
     *
     * This function does not return to its internal call site, it will return directly to the external caller.
     */
    function _fallback() internal virtual {
        _beforeFallback();
        _delegate(_implementation());
    }

    /**
     * @dev Fallback function that delegates calls to the address returned by `_implementation()`. Will run if no other
     * function in the contract matches the call data.
     */
    fallback() external payable virtual {
        _fallback();
    }

    /**
     * @dev Fallback function that delegates calls to the address returned by `_implementation()`. Will run if call data
     * is empty.
     */
    receive() external payable virtual {
        _fallback();
    }

    /**
     * @dev Hook that is called before falling back to the implementation. Can happen as part of a manual `_fallback`
     * call, or as part of the Solidity `fallback` or `receive` functions.
     *
     * If overridden should call `super._beforeFallback()`.
     */
    function _beforeFallback() internal virtual {}
}

// File: node_modules/@openzeppelin/contracts/utils/Address.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.8.0) (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 functionCallWithValue(target, data, 0, "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");
        (bool success, bytes memory returndata) = target.call{value: value}(data);
        return verifyCallResultFromTarget(target, 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) {
        (bool success, bytes memory returndata) = target.staticcall(data);
        return verifyCallResultFromTarget(target, 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) {
        (bool success, bytes memory returndata) = target.delegatecall(data);
        return verifyCallResultFromTarget(target, success, returndata, errorMessage);
    }

    /**
     * @dev Tool to verify that a low level call to smart-contract was successful, and revert (either by bubbling
     * the revert reason or using the provided one) in case of unsuccessful call or if target was not a contract.
     *
     * _Available since v4.8._
     */
    function verifyCallResultFromTarget(
        address target,
        bool success,
        bytes memory returndata,
        string memory errorMessage
    ) internal view returns (bytes memory) {
        if (success) {
            if (returndata.length == 0) {
                // only check isContract if the call was successful and the return data is empty
                // otherwise we already know that it was a contract
                require(isContract(target), "Address: call to non-contract");
            }
            return returndata;
        } else {
            _revert(returndata, errorMessage);
        }
    }

    /**
     * @dev Tool to verify that a low level call was successful, and revert if it wasn't, either by bubbling the
     * revert reason or 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 {
            _revert(returndata, errorMessage);
        }
    }

    function _revert(bytes memory returndata, string memory errorMessage) private pure {
        // 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: node_modules/@openzeppelin/contracts/utils/StorageSlot.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (utils/StorageSlot.sol)

pragma solidity ^0.8.0;

/**
 * @dev Library for reading and writing primitive types to specific storage slots.
 *
 * Storage slots are often used to avoid storage conflict when dealing with upgradeable contracts.
 * This library helps with reading and writing to such slots without the need for inline assembly.
 *
 * The functions in this library return Slot structs that contain a `value` member that can be used to read or write.
 *
 * Example usage to set ERC1967 implementation slot:
 * ```
 * contract ERC1967 {
 *     bytes32 internal constant _IMPLEMENTATION_SLOT = 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;
 *
 *     function _getImplementation() internal view returns (address) {
 *         return StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value;
 *     }
 *
 *     function _setImplementation(address newImplementation) internal {
 *         require(Address.isContract(newImplementation), "ERC1967: new implementation is not a contract");
 *         StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value = newImplementation;
 *     }
 * }
 * ```
 *
 * _Available since v4.1 for `address`, `bool`, `bytes32`, and `uint256`._
 */
library StorageSlot {
    struct AddressSlot {
        address value;
    }

    struct BooleanSlot {
        bool value;
    }

    struct Bytes32Slot {
        bytes32 value;
    }

    struct Uint256Slot {
        uint256 value;
    }

    /**
     * @dev Returns an `AddressSlot` with member `value` located at `slot`.
     */
    function getAddressSlot(bytes32 slot) internal pure returns (AddressSlot storage r) {
        /// @solidity memory-safe-assembly
        assembly {
            r.slot := slot
        }
    }

    /**
     * @dev Returns an `BooleanSlot` with member `value` located at `slot`.
     */
    function getBooleanSlot(bytes32 slot) internal pure returns (BooleanSlot storage r) {
        /// @solidity memory-safe-assembly
        assembly {
            r.slot := slot
        }
    }

    /**
     * @dev Returns an `Bytes32Slot` with member `value` located at `slot`.
     */
    function getBytes32Slot(bytes32 slot) internal pure returns (Bytes32Slot storage r) {
        /// @solidity memory-safe-assembly
        assembly {
            r.slot := slot
        }
    }

    /**
     * @dev Returns an `Uint256Slot` with member `value` located at `slot`.
     */
    function getUint256Slot(bytes32 slot) internal pure returns (Uint256Slot storage r) {
        /// @solidity memory-safe-assembly
        assembly {
            r.slot := slot
        }
    }
}