def stop(self):
        """
        Stop trying to connect and disconnect any current connection.

        @return: a L{Deferred} that fires when all outstanding connections are
            closed and all in-progress connection attempts halted.
        """

        Stop trying to connect and disconnect any current connection.

        @return: a L{Deferred} that fires when all outstanding connections are
            closed and all in-progress connection attempts halted.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/application/internet.py