def test_localToRemoteForwardingV6(self):
        """
        Forwarding of arbitrary IPv6 TCP connections via SSH.
        """
        localPort = self._getFreePort()
        process = ConchTestForwardingProcess(localPort, b'test\n')
        d = self.execute('', process,
                         sshArgs='-N -L%i:[::1]:%i'
                         % (localPort, self.echoPortV6))
        d.addCallback(self.assertEqual, b'test\n')
        return d

        Forwarding of arbitrary IPv6 TCP connections via SSH.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/conch/test/test_conch.py