def test_remoteToLocalForwarding(self):
        """
        Test that we can use whatever client to forward a port from the server
        to a port locally.
        """
        localPort = self._getFreePort()
        process = ConchTestForwardingProcess(localPort, b'test\n')
        d = self.execute('', process,
                         sshArgs='-N -R %i:127.0.0.1:%i'
                         % (localPort, self.echoPort))
        d.addCallback(self.assertEqual, b'test\n')
        return d

        Test that we can use whatever client to forward a port from the server
        to a port locally.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/conch/test/test_conch.py