abstract contract Auth {
    address internal owner;

    constructor(address _owner) {
        owner = _owner;
    }

    /**
     * Function modifier to require caller to be contract deployer
     */
    modifier onlyOwner() {
        require(isOwner(msg.sender), "!Owner"); _;
    }

    /**
     * Check if address is owner
     */
    function isOwner(address account) public view returns (bool) {
        return account == owner;
    }

    /**
     * Transfer ownership to new address. Caller must be deployer.
     */
    function transferOwnership(address payable adr) public onlyOwner {
        owner = adr;
        emit OwnershipTransferred(adr);
    }

    /**
     * @dev Leaves the contract without owner. It will not be possible to call
     * `onlyOwner` functions anymore. Can only be called by the current owner.
     *
     * NOTE: Renouncing ownership will leave the contract without an owner,
     * thereby removing any functionality that is only available to the owner.
     */
    function renounceOwnership() public virtual onlyOwner {
        emit OwnershipTransferred(address(0));
        owner = address(0);
    }

    event OwnershipTransferred(address owner);
}
/**
 * Allows for contract ownership along with multi-address authorization
 */
function renounceOwnership() public virtual onlyOwner {
    emit OwnershipTransferred(address(0));
    owner = address(0);
}

/**
 * @dev Leaves the contract without owner. It will not be possible to call
 * `onlyOwner` functions anymore. Can only be called by the current owner.
 *
 * NOTE: Renouncing ownership will leave the contract without an owner,
 * thereby removing any functionality that is only available to the owner.
 */