contract Ownable {
    address public owner;
    event OwnershipTransferred(
        address indexed previousOwner,
        address indexed newOwner
    );

    /**
  * @dev The Ownable constructor sets the original `owner` of the contract to the sender
  * account.
  */
    function Ownable()public {
        owner = msg.sender;
    }
    /**
  * @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 != address(0));
        emit OwnershipTransferred(owner, newOwner);
        owner = newOwner;
    }
}
/**
 * @title Ownable
 * @dev The Ownable contract has an owner address, and provides basic authorization control
 * functions, this simplifies the implementation of "user permissions".
 */
function Ownable()public {
        owner = msg.sender;
    }
/**
 * @dev The Ownable constructor sets the original `owner` of the contract to the sender
 * account.
 */