def test_sendSimplestPersistentRequest(self):
        """
        A pesistent request does not send 'Connection: close' header.
        """
        req = Request(b'GET', b'/', _boringHeaders, None, persistent=True)
        req.writeTo(self.transport)
        self.assertEqual(
            self.transport.value(),
            b"GET / HTTP/1.1\r\n"
            b"Host: example.com\r\n"
            b"\r\n")

        A pesistent request does not send 'Connection: close' header.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/web/test/test_newclient.py