def test_writerPolling(self):
        """
        Adding a writer causes its C{doWrite} to be called every 1
        milliseconds.
        """
        reactor = Clock()
        poller = _ContinuousPolling(reactor)
        desc = Descriptor()
        poller.addWriter(desc)
        self.assertEqual(desc.events, [])
        reactor.advance(0.001)
        self.assertEqual(desc.events, ["write"])
        reactor.advance(0.001)
        self.assertEqual(desc.events, ["write", "write"])
        reactor.advance(0.001)
        self.assertEqual(desc.events, ["write", "write", "write"])

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