def test_getWriters(self):
        """
        L{_ContinuousPolling.getWriters} returns a list of the write
        descriptors.
        """
        poller = _ContinuousPolling(Clock())
        writer = object()
        poller.addWriter(writer)
        self.assertIn(writer, poller.getWriters())

        L{_ContinuousPolling.getWriters} returns a list of the write
        descriptors.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/internet/test/test_epollreactor.py