ETH Price: $1,960.78 (+1.47%)

Transaction Decoder

Block:
23137684 at Aug-14-2025 07:04:23 AM +UTC
Transaction Fee:
0.000051095248803716 ETH $0.10
Gas Used:
68,029 Gas / 0.751080404 Gwei

Emitted Events:

166 ShapellaUpgradeNFT.Approval( owner=[Receiver] 0x403e102e31f03ee1e7d4f99db6104119d894b757, approved=0x00000000...000000000, tokenId=229583 )
167 ShapellaUpgradeNFT.Transfer( from=[Receiver] 0x403e102e31f03ee1e7d4f99db6104119d894b757, to=0xeB90EA3B...47A1562B9, tokenId=229583 )
168 0x403e102e31f03ee1e7d4f99db6104119d894b757.0x2b9b55e166725f5cc6002ba529baa08d29e675a69d0da2b81faa4addf269c556( 0x2b9b55e166725f5cc6002ba529baa08d29e675a69d0da2b81faa4addf269c556, 0x000000000000000000000000403e102e31f03ee1e7d4f99db6104119d894b757, 0x0000000000000000000000005f04d47d698f79d76f85e835930170ff4c4ebdb7, 0x000000000000000000000000eb90ea3b97405e7ea558ac1bc0fc05447a1562b9, 00000000000000000000000000000000000000000000000000000000000380cf, 0000000000000000000000000000000000000000000000000000000000000001 )

Account State Difference:

  Address   Before After State Difference Code
(Lido: Execution Layer Rewards Vault)
65.449104849045068558 Eth65.449104849521271558 Eth0.000000000476203
0x403E102e...9D894b757 From: 22892027069488871726777845421492261844457874613051320068 To: 22892027013978595914036968185549489350883450254995965128
0x5f04D47D...f4c4EBdB7
0xA18DdadA...2d01bdFAf
0.001569571518325926 Eth
Nonce: 938
0.00151847626952221 Eth
Nonce: 939
0.000051095248803716

Execution Trace

0x403e102e31f03ee1e7d4f99db6104119d894b757.789f93f6( )
  • ShapellaUpgradeNFT.safeTransferFrom( from=0x403E102e31f03ee1e7d4F99dB6104119D894b757, to=0xeB90EA3B97405e7eA558aC1Bc0fc05447A1562B9, tokenId=229583 )
    /**********************************************************************************************************
      ____|  |    |                                             ____|              |                   | 
      __|    __|  __ \\    _ \\   __|  _ \\  |   |  __ `__ \\       __| \\ \\   /  _ \\   | \\ \\   /  _ \\   _` | 
      |      |    | | |   __/  |     __/  |   |  |   |   |      |    \\ \\ /  (   |  |  \\ \\ /   __/  (   | 
     _____| \\__| _| |_| \\___| _|   \\___| \\__,_| _|  _|  _|     _____| \\_/  \\___/  _|   \\_/  \\___| \\__,_| 
          ___           ___           ___           ___           ___           ___       ___       ___     
         /\\  \\         /\\__\\         /\\  \\         /\\  \\         /\\  \\         /\\__\\     /\\__\\     /\\  \\    
        /::\\  \\       /:/  /        /::\\  \\       /::\\  \\       /::\\  \\       /:/  /    /:/  /    /::\\  \\   
       /:/\\ \\  \\     /:/__/        /:/\\:\\  \\     /:/\\:\\  \\     /:/\\:\\  \\     /:/  /    /:/  /    /:/\\:\\  \\  
      _\\:\\~\\ \\  \\   /::\\  \\ ___   /::\\~\\:\\  \\   /::\\~\\:\\  \\   /::\\~\\:\\  \\   /:/  /    /:/  /    /::\\~\\:\\  \\ 
     /\\ \\:\\ \\ \\__\\ /:/\\:\\  /\\__\\ /:/\\:\\ \\:\\__\\ /:/\\:\\ \\:\\__\\ /:/\\:\\ \\:\\__\\ /:/__/    /:/__/    /:/\\:\\ \\:\\__\\
     \\:\\ \\:\\ \\/__/ \\/__\\:\\/:/  / \\/__\\:\\/:/  / \\/__\\:\\/:/  / \\:\\~\\:\\ \\/__/ \\:\\  \\    \\:\\  \\    \\/__\\:\\/:/  /
      \\:\\ \\:\\__\\        \\::/  /       \\::/  /       \\::/  /   \\:\\ \\:\\__\\    \\:\\  \\    \\:\\  \\        \\::/  / 
       \\:\\/:/  /        /:/  /        /:/  /         \\/__/     \\:\\ \\/__/     \\:\\  \\    \\:\\  \\       /:/  /  
        \\::/  /        /:/  /        /:/  /                     \\:\\__\\        \\:\\__\\    \\:\\__\\     /:/  /   
         \\/__/         \\/__/         \\/__/                       \\/__/         \\/__/     \\/__/     \\/__/   
    **********************************************************************************************************/
    pragma solidity 0.8.19;
    import "@openzeppelin/contracts/token/ERC721/ERC721.sol";
    import "@openzeppelin/contracts/access/Ownable.sol";
    /**
     * @dev Revert with an error when the mint is not active
     */
    error MintNotActive();
    /**
     * @dev Revert with an error mint to recipients count does not match supply
     */
    error RecipientLengthDoesNotMatchSupply();
    /**
     * @dev Revert with an error when trying to set the mint active when it was already set active
     */
    error AlreadySetActive();
    /**
     * @dev Revert with an error when trying to mint an invalid token
     */
    error InvalidToken();
    /**
     * @dev Revert if we've minted all the tokens
     */
    error SoldOut();
    /**
     * @dev Revert if we have frozen setting URIs
     */
    error TokenUrisFrozen();
    contract ShapellaUpgradeNFT is ERC721, Ownable {
        string private CONTRIBUTOR_TOKEN_URI;
        string private OPEN_EDITION_TOKEN_URI;
        uint128 private constant CONTRIBUTOR_SUPPLY = 128;
        uint128 private constant CONTRIBUTOR_STARTING_TOKEN_ID = 1;
        uint128 private constant OPEN_EDITION_STARTING_TOKEN_ID = CONTRIBUTOR_SUPPLY + CONTRIBUTOR_STARTING_TOKEN_ID;
        uint64 private constant OPEN_EDITION_LENGTH = 3 days;
        uint128 private nextTokenId = OPEN_EDITION_STARTING_TOKEN_ID;
        uint64 public mintOpenUntil;
        // Until true, admins can set token URIs
        bool public isFrozen = false;
        constructor(
            string memory contributorTokenUri,
            string memory openEditionTokenUri
        ) ERC721("ShapellaUpgrade", "SHAPELLA") {
            CONTRIBUTOR_TOKEN_URI = contributorTokenUri;
            OPEN_EDITION_TOKEN_URI = openEditionTokenUri;
        }
        /**
         * @notice Mint an open edition NFT - restricted to a specific time window
         */
        function publicMint() external {
            if (block.timestamp > mintOpenUntil) {
                revert MintNotActive();
            }
            if (nextTokenId == type(uint128).max) {
                revert SoldOut();
            }
            _mint(_msgSender(), nextTokenId++);
        }
        /**
         * @notice See {IERC721Metadata-tokenURI}.
         */
        function tokenURI(uint256 tokenId) public view virtual override returns (string memory) {
            if (tokenId < OPEN_EDITION_STARTING_TOKEN_ID) {
                return CONTRIBUTOR_TOKEN_URI;
            }
            _requireMinted(tokenId);
            return OPEN_EDITION_TOKEN_URI;
        }
        /**
         * @notice Set the open edition mint to active
         * @dev Restricted to admins. Cannot set active more than once.
         */
        function setActive() external {
            if (mintOpenUntil != 0) {
                revert AlreadySetActive();
            }
            mintOpenUntil = uint64(block.timestamp) + OPEN_EDITION_LENGTH;
        }
        /**
         * @notice Mint a token
         * @dev Restricted to admins.
         * @param tokenId The token to mint
         * @param recipient The address to mint the token to
         */
        function adminMintTo(uint256 tokenId, address recipient) external onlyOwner {
            if (tokenId >= OPEN_EDITION_STARTING_TOKEN_ID) {
                revert InvalidToken();
            }
            _mint(recipient, tokenId);
        }
        /**
         * @notice Mint contributor NFTs
         * @dev Restricted to admins
         * @param recipients The recipient addresses to mint the tokens to
         */
        function adminMintContributorNfts(address[] memory recipients) external onlyOwner {
            if (recipients.length != CONTRIBUTOR_SUPPLY) {
                revert RecipientLengthDoesNotMatchSupply();
            }
            for (uint256 i = 0; i < CONTRIBUTOR_SUPPLY; i++) {
                _mint(recipients[i], CONTRIBUTOR_STARTING_TOKEN_ID + i);
            }
        }
        /**
         * @notice Set token URIs
         * @dev Restricted to admins
         * @param contributorTokenUri CONTRIBUTOR_TOKEN_URI value
         * @param openEditionTokenUri OPEN_EDITION_TOKEN_URI value
         */
        function adminSetTokenUris(
            string memory contributorTokenUri,
            string memory openEditionTokenUri
        ) external onlyOwner {
            if (isFrozen == true) {
                revert TokenUrisFrozen();
            }
            CONTRIBUTOR_TOKEN_URI = contributorTokenUri;
            OPEN_EDITION_TOKEN_URI = openEditionTokenUri;
        }
        /**
         * @notice Sets isFrozen flag to true
         * @dev Restricted to admins; cannot be undone
         */
        function adminSetFrozen() external onlyOwner {
            isFrozen = true;
        }
    }
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts (last updated v4.7.0) (token/ERC721/ERC721.sol)
    pragma solidity ^0.8.0;
    import "./IERC721.sol";
    import "./IERC721Receiver.sol";
    import "./extensions/IERC721Metadata.sol";
    import "../../utils/Address.sol";
    import "../../utils/Context.sol";
    import "../../utils/Strings.sol";
    import "../../utils/introspection/ERC165.sol";
    /**
     * @dev Implementation of https://eips.ethereum.org/EIPS/eip-721[ERC721] Non-Fungible Token Standard, including
     * the Metadata extension, but not including the Enumerable extension, which is available separately as
     * {ERC721Enumerable}.
     */
    contract ERC721 is Context, ERC165, IERC721, IERC721Metadata {
        using Address for address;
        using Strings for uint256;
        // Token name
        string private _name;
        // Token symbol
        string private _symbol;
        // Mapping from token ID to owner address
        mapping(uint256 => address) private _owners;
        // Mapping owner address to token count
        mapping(address => uint256) private _balances;
        // Mapping from token ID to approved address
        mapping(uint256 => address) private _tokenApprovals;
        // Mapping from owner to operator approvals
        mapping(address => mapping(address => bool)) private _operatorApprovals;
        /**
         * @dev Initializes the contract by setting a `name` and a `symbol` to the token collection.
         */
        constructor(string memory name_, string memory symbol_) {
            _name = name_;
            _symbol = symbol_;
        }
        /**
         * @dev See {IERC165-supportsInterface}.
         */
        function supportsInterface(bytes4 interfaceId) public view virtual override(ERC165, IERC165) returns (bool) {
            return
                interfaceId == type(IERC721).interfaceId ||
                interfaceId == type(IERC721Metadata).interfaceId ||
                super.supportsInterface(interfaceId);
        }
        /**
         * @dev See {IERC721-balanceOf}.
         */
        function balanceOf(address owner) public view virtual override returns (uint256) {
            require(owner != address(0), "ERC721: address zero is not a valid owner");
            return _balances[owner];
        }
        /**
         * @dev See {IERC721-ownerOf}.
         */
        function ownerOf(uint256 tokenId) public view virtual override returns (address) {
            address owner = _owners[tokenId];
            require(owner != address(0), "ERC721: invalid token ID");
            return owner;
        }
        /**
         * @dev See {IERC721Metadata-name}.
         */
        function name() public view virtual override returns (string memory) {
            return _name;
        }
        /**
         * @dev See {IERC721Metadata-symbol}.
         */
        function symbol() public view virtual override returns (string memory) {
            return _symbol;
        }
        /**
         * @dev See {IERC721Metadata-tokenURI}.
         */
        function tokenURI(uint256 tokenId) public view virtual override returns (string memory) {
            _requireMinted(tokenId);
            string memory baseURI = _baseURI();
            return bytes(baseURI).length > 0 ? string(abi.encodePacked(baseURI, tokenId.toString())) : "";
        }
        /**
         * @dev Base URI for computing {tokenURI}. If set, the resulting URI for each
         * token will be the concatenation of the `baseURI` and the `tokenId`. Empty
         * by default, can be overridden in child contracts.
         */
        function _baseURI() internal view virtual returns (string memory) {
            return "";
        }
        /**
         * @dev See {IERC721-approve}.
         */
        function approve(address to, uint256 tokenId) public virtual override {
            address owner = ERC721.ownerOf(tokenId);
            require(to != owner, "ERC721: approval to current owner");
            require(
                _msgSender() == owner || isApprovedForAll(owner, _msgSender()),
                "ERC721: approve caller is not token owner nor approved for all"
            );
            _approve(to, tokenId);
        }
        /**
         * @dev See {IERC721-getApproved}.
         */
        function getApproved(uint256 tokenId) public view virtual override returns (address) {
            _requireMinted(tokenId);
            return _tokenApprovals[tokenId];
        }
        /**
         * @dev See {IERC721-setApprovalForAll}.
         */
        function setApprovalForAll(address operator, bool approved) public virtual override {
            _setApprovalForAll(_msgSender(), operator, approved);
        }
        /**
         * @dev See {IERC721-isApprovedForAll}.
         */
        function isApprovedForAll(address owner, address operator) public view virtual override returns (bool) {
            return _operatorApprovals[owner][operator];
        }
        /**
         * @dev See {IERC721-transferFrom}.
         */
        function transferFrom(
            address from,
            address to,
            uint256 tokenId
        ) public virtual override {
            //solhint-disable-next-line max-line-length
            require(_isApprovedOrOwner(_msgSender(), tokenId), "ERC721: caller is not token owner nor approved");
            _transfer(from, to, tokenId);
        }
        /**
         * @dev See {IERC721-safeTransferFrom}.
         */
        function safeTransferFrom(
            address from,
            address to,
            uint256 tokenId
        ) public virtual override {
            safeTransferFrom(from, to, tokenId, "");
        }
        /**
         * @dev See {IERC721-safeTransferFrom}.
         */
        function safeTransferFrom(
            address from,
            address to,
            uint256 tokenId,
            bytes memory data
        ) public virtual override {
            require(_isApprovedOrOwner(_msgSender(), tokenId), "ERC721: caller is not token owner nor approved");
            _safeTransfer(from, to, tokenId, data);
        }
        /**
         * @dev Safely transfers `tokenId` token from `from` to `to`, checking first that contract recipients
         * are aware of the ERC721 protocol to prevent tokens from being forever locked.
         *
         * `data` is additional data, it has no specified format and it is sent in call to `to`.
         *
         * This internal function is equivalent to {safeTransferFrom}, and can be used to e.g.
         * implement alternative mechanisms to perform token transfer, such as signature-based.
         *
         * Requirements:
         *
         * - `from` cannot be the zero address.
         * - `to` cannot be the zero address.
         * - `tokenId` token must exist and be owned by `from`.
         * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
         *
         * Emits a {Transfer} event.
         */
        function _safeTransfer(
            address from,
            address to,
            uint256 tokenId,
            bytes memory data
        ) internal virtual {
            _transfer(from, to, tokenId);
            require(_checkOnERC721Received(from, to, tokenId, data), "ERC721: transfer to non ERC721Receiver implementer");
        }
        /**
         * @dev Returns whether `tokenId` exists.
         *
         * Tokens can be managed by their owner or approved accounts via {approve} or {setApprovalForAll}.
         *
         * Tokens start existing when they are minted (`_mint`),
         * and stop existing when they are burned (`_burn`).
         */
        function _exists(uint256 tokenId) internal view virtual returns (bool) {
            return _owners[tokenId] != address(0);
        }
        /**
         * @dev Returns whether `spender` is allowed to manage `tokenId`.
         *
         * Requirements:
         *
         * - `tokenId` must exist.
         */
        function _isApprovedOrOwner(address spender, uint256 tokenId) internal view virtual returns (bool) {
            address owner = ERC721.ownerOf(tokenId);
            return (spender == owner || isApprovedForAll(owner, spender) || getApproved(tokenId) == spender);
        }
        /**
         * @dev Safely mints `tokenId` and transfers it to `to`.
         *
         * Requirements:
         *
         * - `tokenId` must not exist.
         * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
         *
         * Emits a {Transfer} event.
         */
        function _safeMint(address to, uint256 tokenId) internal virtual {
            _safeMint(to, tokenId, "");
        }
        /**
         * @dev Same as {xref-ERC721-_safeMint-address-uint256-}[`_safeMint`], with an additional `data` parameter which is
         * forwarded in {IERC721Receiver-onERC721Received} to contract recipients.
         */
        function _safeMint(
            address to,
            uint256 tokenId,
            bytes memory data
        ) internal virtual {
            _mint(to, tokenId);
            require(
                _checkOnERC721Received(address(0), to, tokenId, data),
                "ERC721: transfer to non ERC721Receiver implementer"
            );
        }
        /**
         * @dev Mints `tokenId` and transfers it to `to`.
         *
         * WARNING: Usage of this method is discouraged, use {_safeMint} whenever possible
         *
         * Requirements:
         *
         * - `tokenId` must not exist.
         * - `to` cannot be the zero address.
         *
         * Emits a {Transfer} event.
         */
        function _mint(address to, uint256 tokenId) internal virtual {
            require(to != address(0), "ERC721: mint to the zero address");
            require(!_exists(tokenId), "ERC721: token already minted");
            _beforeTokenTransfer(address(0), to, tokenId);
            _balances[to] += 1;
            _owners[tokenId] = to;
            emit Transfer(address(0), to, tokenId);
            _afterTokenTransfer(address(0), to, tokenId);
        }
        /**
         * @dev Destroys `tokenId`.
         * The approval is cleared when the token is burned.
         *
         * Requirements:
         *
         * - `tokenId` must exist.
         *
         * Emits a {Transfer} event.
         */
        function _burn(uint256 tokenId) internal virtual {
            address owner = ERC721.ownerOf(tokenId);
            _beforeTokenTransfer(owner, address(0), tokenId);
            // Clear approvals
            _approve(address(0), tokenId);
            _balances[owner] -= 1;
            delete _owners[tokenId];
            emit Transfer(owner, address(0), tokenId);
            _afterTokenTransfer(owner, address(0), tokenId);
        }
        /**
         * @dev Transfers `tokenId` from `from` to `to`.
         *  As opposed to {transferFrom}, this imposes no restrictions on msg.sender.
         *
         * Requirements:
         *
         * - `to` cannot be the zero address.
         * - `tokenId` token must be owned by `from`.
         *
         * Emits a {Transfer} event.
         */
        function _transfer(
            address from,
            address to,
            uint256 tokenId
        ) internal virtual {
            require(ERC721.ownerOf(tokenId) == from, "ERC721: transfer from incorrect owner");
            require(to != address(0), "ERC721: transfer to the zero address");
            _beforeTokenTransfer(from, to, tokenId);
            // Clear approvals from the previous owner
            _approve(address(0), tokenId);
            _balances[from] -= 1;
            _balances[to] += 1;
            _owners[tokenId] = to;
            emit Transfer(from, to, tokenId);
            _afterTokenTransfer(from, to, tokenId);
        }
        /**
         * @dev Approve `to` to operate on `tokenId`
         *
         * Emits an {Approval} event.
         */
        function _approve(address to, uint256 tokenId) internal virtual {
            _tokenApprovals[tokenId] = to;
            emit Approval(ERC721.ownerOf(tokenId), to, tokenId);
        }
        /**
         * @dev Approve `operator` to operate on all of `owner` tokens
         *
         * Emits an {ApprovalForAll} event.
         */
        function _setApprovalForAll(
            address owner,
            address operator,
            bool approved
        ) internal virtual {
            require(owner != operator, "ERC721: approve to caller");
            _operatorApprovals[owner][operator] = approved;
            emit ApprovalForAll(owner, operator, approved);
        }
        /**
         * @dev Reverts if the `tokenId` has not been minted yet.
         */
        function _requireMinted(uint256 tokenId) internal view virtual {
            require(_exists(tokenId), "ERC721: invalid token ID");
        }
        /**
         * @dev Internal function to invoke {IERC721Receiver-onERC721Received} on a target address.
         * The call is not executed if the target address is not a contract.
         *
         * @param from address representing the previous owner of the given token ID
         * @param to target address that will receive the tokens
         * @param tokenId uint256 ID of the token to be transferred
         * @param data bytes optional data to send along with the call
         * @return bool whether the call correctly returned the expected magic value
         */
        function _checkOnERC721Received(
            address from,
            address to,
            uint256 tokenId,
            bytes memory data
        ) private returns (bool) {
            if (to.isContract()) {
                try IERC721Receiver(to).onERC721Received(_msgSender(), from, tokenId, data) returns (bytes4 retval) {
                    return retval == IERC721Receiver.onERC721Received.selector;
                } catch (bytes memory reason) {
                    if (reason.length == 0) {
                        revert("ERC721: transfer to non ERC721Receiver implementer");
                    } else {
                        /// @solidity memory-safe-assembly
                        assembly {
                            revert(add(32, reason), mload(reason))
                        }
                    }
                }
            } else {
                return true;
            }
        }
        /**
         * @dev Hook that is called before any token transfer. This includes minting
         * and burning.
         *
         * Calling conditions:
         *
         * - When `from` and `to` are both non-zero, ``from``'s `tokenId` will be
         * transferred to `to`.
         * - When `from` is zero, `tokenId` will be minted for `to`.
         * - When `to` is zero, ``from``'s `tokenId` 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 tokenId
        ) 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.
         * - `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 tokenId
        ) internal virtual {}
    }
    // 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 (last updated v4.7.0) (token/ERC721/IERC721.sol)
    pragma solidity ^0.8.0;
    import "../../utils/introspection/IERC165.sol";
    /**
     * @dev Required interface of an ERC721 compliant contract.
     */
    interface IERC721 is IERC165 {
        /**
         * @dev Emitted when `tokenId` token is transferred from `from` to `to`.
         */
        event Transfer(address indexed from, address indexed to, uint256 indexed tokenId);
        /**
         * @dev Emitted when `owner` enables `approved` to manage the `tokenId` token.
         */
        event Approval(address indexed owner, address indexed approved, uint256 indexed tokenId);
        /**
         * @dev Emitted when `owner` enables or disables (`approved`) `operator` to manage all of its assets.
         */
        event ApprovalForAll(address indexed owner, address indexed operator, bool approved);
        /**
         * @dev Returns the number of tokens in ``owner``'s account.
         */
        function balanceOf(address owner) external view returns (uint256 balance);
        /**
         * @dev Returns the owner of the `tokenId` token.
         *
         * Requirements:
         *
         * - `tokenId` must exist.
         */
        function ownerOf(uint256 tokenId) external view returns (address owner);
        /**
         * @dev Safely transfers `tokenId` token from `from` to `to`.
         *
         * Requirements:
         *
         * - `from` cannot be the zero address.
         * - `to` cannot be the zero address.
         * - `tokenId` token must exist and be owned by `from`.
         * - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.
         * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
         *
         * Emits a {Transfer} event.
         */
        function safeTransferFrom(
            address from,
            address to,
            uint256 tokenId,
            bytes calldata data
        ) external;
        /**
         * @dev Safely transfers `tokenId` token from `from` to `to`, checking first that contract recipients
         * are aware of the ERC721 protocol to prevent tokens from being forever locked.
         *
         * Requirements:
         *
         * - `from` cannot be the zero address.
         * - `to` cannot be the zero address.
         * - `tokenId` token must exist and be owned by `from`.
         * - If the caller is not `from`, it must have been allowed to move this token by either {approve} or {setApprovalForAll}.
         * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
         *
         * Emits a {Transfer} event.
         */
        function safeTransferFrom(
            address from,
            address to,
            uint256 tokenId
        ) external;
        /**
         * @dev Transfers `tokenId` token from `from` to `to`.
         *
         * WARNING: Usage of this method is discouraged, use {safeTransferFrom} whenever possible.
         *
         * Requirements:
         *
         * - `from` cannot be the zero address.
         * - `to` cannot be the zero address.
         * - `tokenId` token must be owned by `from`.
         * - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.
         *
         * Emits a {Transfer} event.
         */
        function transferFrom(
            address from,
            address to,
            uint256 tokenId
        ) external;
        /**
         * @dev Gives permission to `to` to transfer `tokenId` token to another account.
         * The approval is cleared when the token is transferred.
         *
         * Only a single account can be approved at a time, so approving the zero address clears previous approvals.
         *
         * Requirements:
         *
         * - The caller must own the token or be an approved operator.
         * - `tokenId` must exist.
         *
         * Emits an {Approval} event.
         */
        function approve(address to, uint256 tokenId) external;
        /**
         * @dev Approve or remove `operator` as an operator for the caller.
         * Operators can call {transferFrom} or {safeTransferFrom} for any token owned by the caller.
         *
         * Requirements:
         *
         * - The `operator` cannot be the caller.
         *
         * Emits an {ApprovalForAll} event.
         */
        function setApprovalForAll(address operator, bool _approved) external;
        /**
         * @dev Returns the account approved for `tokenId` token.
         *
         * Requirements:
         *
         * - `tokenId` must exist.
         */
        function getApproved(uint256 tokenId) external view returns (address operator);
        /**
         * @dev Returns if the `operator` is allowed to manage all of the assets of `owner`.
         *
         * See {setApprovalForAll}
         */
        function isApprovedForAll(address owner, address operator) external view returns (bool);
    }
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts (last updated v4.6.0) (token/ERC721/IERC721Receiver.sol)
    pragma solidity ^0.8.0;
    /**
     * @title ERC721 token receiver interface
     * @dev Interface for any contract that wants to support safeTransfers
     * from ERC721 asset contracts.
     */
    interface IERC721Receiver {
        /**
         * @dev Whenever an {IERC721} `tokenId` token is transferred to this contract via {IERC721-safeTransferFrom}
         * by `operator` from `from`, this function is called.
         *
         * It must return its Solidity selector to confirm the token transfer.
         * If any other value is returned or the interface is not implemented by the recipient, the transfer will be reverted.
         *
         * The selector can be obtained in Solidity with `IERC721Receiver.onERC721Received.selector`.
         */
        function onERC721Received(
            address operator,
            address from,
            uint256 tokenId,
            bytes calldata data
        ) external returns (bytes4);
    }
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts v4.4.1 (token/ERC721/extensions/IERC721Metadata.sol)
    pragma solidity ^0.8.0;
    import "../IERC721.sol";
    /**
     * @title ERC-721 Non-Fungible Token Standard, optional metadata extension
     * @dev See https://eips.ethereum.org/EIPS/eip-721
     */
    interface IERC721Metadata is IERC721 {
        /**
         * @dev Returns the token collection name.
         */
        function name() external view returns (string memory);
        /**
         * @dev Returns the token collection symbol.
         */
        function symbol() external view returns (string memory);
        /**
         * @dev Returns the Uniform Resource Identifier (URI) for `tokenId` token.
         */
        function tokenURI(uint256 tokenId) external view returns (string memory);
    }
    // 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 v4.4.1 (utils/introspection/ERC165.sol)
    pragma solidity ^0.8.0;
    import "./IERC165.sol";
    /**
     * @dev Implementation of the {IERC165} interface.
     *
     * Contracts that want to implement ERC165 should inherit from this contract and override {supportsInterface} to check
     * for the additional interface id that will be supported. For example:
     *
     * ```solidity
     * function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
     *     return interfaceId == type(MyInterface).interfaceId || super.supportsInterface(interfaceId);
     * }
     * ```
     *
     * Alternatively, {ERC165Storage} provides an easier to use but more expensive implementation.
     */
    abstract contract ERC165 is IERC165 {
        /**
         * @dev See {IERC165-supportsInterface}.
         */
        function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
            return interfaceId == type(IERC165).interfaceId;
        }
    }
    // 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);
    }