def test_rrheader(self):
        """
        Two L{dns.RRHeader} instances compare equal if and only if they have
        the same name, type, class, time to live, payload, and authoritative
        bit.
        """
        # Vary the name
        self._equalityTest(
            dns.RRHeader(b'example.com', payload=dns.Record_A('1.2.3.4')),
            dns.RRHeader(b'example.com', payload=dns.Record_A('1.2.3.4')),
            dns.RRHeader(b'example.org', payload=dns.Record_A('1.2.3.4')))

        # Vary the payload
        self._equalityTest(
            dns.RRHeader(b'example.com', payload=dns.Record_A('1.2.3.4')),
            dns.RRHeader(b'example.com', payload=dns.Record_A('1.2.3.4')),
            dns.RRHeader(b'example.com', payload=dns.Record_A('1.2.3.5')))

        # Vary the type.  Leave the payload as None so that we don't have to
        # provide non-equal values.
        self._equalityTest(
            dns.RRHeader(b'example.com', dns.A),
            dns.RRHeader(b'example.com', dns.A),
            dns.RRHeader(b'example.com', dns.MX))

        # Probably not likely to come up.  Most people use the internet.
        self._equalityTest(
            dns.RRHeader(b'example.com', cls=dns.IN, payload=dns.Record_A('1.2.3.4')),
            dns.RRHeader(b'example.com', cls=dns.IN, payload=dns.Record_A('1.2.3.4')),
            dns.RRHeader(b'example.com', cls=dns.CS, payload=dns.Record_A('1.2.3.4')))

        # Vary the ttl
        self._equalityTest(
            dns.RRHeader(b'example.com', ttl=60, payload=dns.Record_A('1.2.3.4')),
            dns.RRHeader(b'example.com', ttl=60, payload=dns.Record_A('1.2.3.4')),
            dns.RRHeader(b'example.com', ttl=120, payload=dns.Record_A('1.2.3.4')))

        # Vary the auth bit
        self._equalityTest(
            dns.RRHeader(b'example.com', auth=1, payload=dns.Record_A('1.2.3.4')),
            dns.RRHeader(b'example.com', auth=1, payload=dns.Record_A('1.2.3.4')),
            dns.RRHeader(b'example.com', auth=0, payload=dns.Record_A('1.2.3.4')))

        Two L{dns.RRHeader} instances compare equal if and only if they have
        the same name, type, class, time to live, payload, and authoritative
        bit.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/names/test/test_dns.py