def test_ednsDecode(self):
        """
        The L(_EDNSMessage} instance created by L{dns._EDNSMessage.fromStr}
        derives its edns specific values (C{ednsVersion}, etc) from the supplied
        OPT record.
        """
        m = self.messageFactory()
        m.fromStr(MessageEDNSComplete.bytes())

        self.assertEqual(m, self.messageFactory(**MessageEDNSComplete.kwargs()))

        The L(_EDNSMessage} instance created by L{dns._EDNSMessage.fromStr}
        derives its edns specific values (C{ednsVersion}, etc) from the supplied
        OPT record.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/names/test/test_dns.py