def test_readerPolling(self):
        """
        Adding a reader causes its C{doRead} to be called every 1
        milliseconds.
        """
        reactor = Clock()
        poller = _ContinuousPolling(reactor)
        desc = Descriptor()
        poller.addReader(desc)
        self.assertEqual(desc.events, [])
        reactor.advance(0.00001)
        self.assertEqual(desc.events, ["read"])
        reactor.advance(0.00001)
        self.assertEqual(desc.events, ["read", "read"])
        reactor.advance(0.00001)
        self.assertEqual(desc.events, ["read", "read", "read"])

        Adding a reader causes its C{doRead} to be called every 1
        milliseconds.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/internet/test/test_epollreactor.py