// SPDX-License-Identifier: MIT
pragma solidity ^0.8.13;

import "@openzeppelin/contracts/interfaces/IERC165.sol";

interface IContractEntity is IERC165 {
    /**
     * @dev Thrown when contract entity does not implement the required interface.
     */
    error InvalidContractEntityInterface();

    /**
     * @dev Returns implemented contract key.
     * @return Contract key;
     */
    function contractKey() external pure returns (bytes4);
}