def test_resumeProducing(self):
        """
        L{StringTransport.resumeProducing} changes the C{producerState} of the
        transport to C{'producing'}.
        """
        self.transport.pauseProducing()
        self.transport.resumeProducing()
        self.assertEqual(self.transport.producerState, 'producing')

        L{StringTransport.resumeProducing} changes the C{producerState} of the
        transport to C{'producing'}.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/internet/test/test_testing.py