contract.sol

contract ReverseResolver is CustomContext {
 	mapping (address => uint256) reverses;
IERC721 registry;

	constructor(address_registry) {
	registry = IERC721(_registry);
}

function reverseOf(address account) public view returns (uint256) {
	uint tokenId = reverses[account];
	require(registry.ownerOf(tokenId) == account);
	return tokenId;
}

function registerReverse(uint256 tokenId) public {
address sender = _msgSender();
	require(registry.ownerOf(tokenId) == sender);
	reverses[sender] = tokenId;
}
}