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 `IERC721.onERC721Received.selector`.
   */
  function onERC721Received(
    address operator,
    address from,
    uint256 tokenId,
    bytes calldata data
  ) external returns (bytes4);
}
/**
 * @title ERC721 token receiver interface
 * @dev Interface for any contract that wants to support safeTransfers
 * from ERC721 asset contracts.
 */
function onERC721Received(
    address operator,
    address from,
    uint256 tokenId,
    bytes calldata data
  ) external returns (bytes4);
/**
 * @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 `IERC721.onERC721Received.selector`.
 */