def test_helloNoErrorHandling(self):
        """
        Verify that if an unknown error type is raised, it will be relayed to
        the other end of the connection and translated into an exception, it
        will be logged, and then the connection will be dropped.
        """
        L=[]
        c, s, p = connectedServerAndClient(
            ServerClass=SimpleSymmetricCommandProtocol,
            ClientClass=SimpleSymmetricCommandProtocol)
        HELLO = THING_I_DONT_UNDERSTAND
        c.sendHello(HELLO).addErrback(L.append)
        p.flush()
        ure = L.pop()
        ure.trap(amp.UnknownRemoteError)
        c.sendHello(HELLO).addErrback(L.append)
        cl = L.pop()
        cl.trap(error.ConnectionDone)
        # The exception should have been logged.
        self.assertTrue(self.flushLoggedErrors(ThingIDontUnderstandError))

        Verify that if an unknown error type is raised, it will be relayed to
        the other end of the connection and translated into an exception, it
        will be logged, and then the connection will be dropped.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/test/test_amp.py