def test_fullParsingSuccess(self):
        """
        Test that parsing is successful for a PROXY header.
        """
        info = _v1parser.V1Parser.parse(
            b'PROXY TCP4 127.0.0.1 127.0.0.1 8080 8888',
        )
        self.assertIsInstance(info.source, address.IPv4Address)
        self.assertEqual(info.source.host, b'127.0.0.1')
        self.assertEqual(info.source.port, 8080)
        self.assertEqual(info.destination.host, b'127.0.0.1')
        self.assertEqual(info.destination.port, 8888)

        Test that parsing is successful for a PROXY header.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/protocols/haproxy/test/test_v1parser.py