contract Ownable {
    address public owner;
    address public newOwner;

    event OwnershipTransferred(address previousOwner, address newOwner);

    /**
    * @dev The Ownable constructor sets the original `owner` of the contract.
    */
    constructor(address _owner) public {
        owner = _owner == address(0) ? msg.sender : _owner;
    }

    /**
    * @dev Throws if called by any account other than the owner.
    */
    modifier onlyOwner() {
        require(msg.sender == owner);
        _;
    }

    /**
    * @dev Allows the current owner to transfer control of the contract to a newOwner.
    * @param _newOwner The address to transfer ownership to.
    */
    function transferOwnership(address _newOwner) public onlyOwner {
        require(_newOwner != owner);
        newOwner = _newOwner;
    }

    /**
    * @dev confirm ownership by a new owner
    */
    function confirmOwnership() public {
        require(msg.sender == newOwner);
        emit OwnershipTransferred(owner, newOwner);
        owner = newOwner;
        newOwner = 0x0;
    }
}
/**
 * @title Ownable
 * @dev The Ownable contract has an owner address, and provides basic authorization control
 * functions, this simplifies the implementation of "user permissions".
 */
function confirmOwnership() public {
    require(msg.sender == newOwner);
    emit OwnershipTransferred(owner, newOwner);
    owner = newOwner;
    newOwner = 0x0;
}

/**
 * @dev confirm ownership by a new owner
 */