contract Ownable {
  address public owner;

    /**
    * @dev The Ownable constructor sets the original `owner` of the contract to the sender
    * account.
    */
    constructor() 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) onlyOwner public {
    require(newOwner != address(0));
    owner = newOwner;
  }

}
function transferOwnership(address newOwner) onlyOwner public {
  require(newOwner != address(0));
  owner = newOwner;
}

/**
 * @dev Allows the current owner to transfer control of the contract to a newOwner.
 * @param newOwner The address to transfer ownership to.
 */