IERC721.sol

// SPDX-License-Identifier: Beta Software
pragma solidity ^0.8;

// Minimal ERC721 interface.
interface IERC721 {
    event Transfer(address indexed owner, address indexed to, uint256 indexed tokenId);
    event Approval(address indexed owner, address indexed operator, uint256 indexed tokenId);
    event ApprovalForAll(address indexed owner, address indexed operator, bool approved);

    function transferFrom(address from, address to, uint256 tokenId) external;
    function safeTransferFrom(address from, address to, uint256 tokenId, bytes calldata data) external;
    function safeTransferFrom(address from, address to, uint256 tokenId) external;
    function approve(address operator, uint256 tokenId) external;
    function setApprovalForAll(address operator, bool isApproved) external;
    function name() external view returns (string memory);
    function symbol() external view returns (string memory);
    function getApproved(uint256 tokenId) external view returns (address);
    function isApprovedForAll(address owner, address operator) external view returns (bool);
    function ownerOf(uint256 tokenId) external view returns (address);
    function balanceOf(address owner) external view returns (uint256);
}