def test_secondRequest(self):
        """
        The second time L{HTTP11ClientProtocol.request} is called, it returns a
        L{Deferred} which immediately fires with a L{Failure} wrapping a
        L{RequestNotSent} exception.
        """
        self.protocol.request(SlowRequest())
        def cbNotSent(ignored):
            self.assertEqual(self.transport.value(), b'')
        d = self.assertFailure(
            self.protocol.request(SimpleRequest()), RequestNotSent)
        d.addCallback(cbNotSent)
        return d

        The second time L{HTTP11ClientProtocol.request} is called, it returns a
        L{Deferred} which immediately fires with a L{Failure} wrapping a
        L{RequestNotSent} exception.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/web/test/test_newclient.py