'Unregistering a streaming producer removes it, reverting to initial state.'

def test_streamingProducerUnregister(self):

    (clientProtocol, tlsProtocol, producer) = self.setupStreamingProducer()
    clientProtocol.transport.unregisterProducer()
    self.assertIsNone(tlsProtocol._producer)
    self.assertIsNone(tlsProtocol.transport.producer)
