def bytes(cls):
        """
        Bytes which are expected when encoding an instance constructed using
        C{kwargs} and which are expected to result in an identical instance when
        decoded.

        @return: The L{bytes} of a wire encoded message.
        """
        return (
            b'\x01\x00' # id: 256
            b'\x97' # QR: 1, OPCODE: 2, AA: 0, TC: 0, RD: 1
            b'\x8f' # RA: 1, Z, RCODE: 15
            b'\x00\x00' # number of queries
            b'\x00\x00' # number of answers
            b'\x00\x00' # number of authorities
            b'\x00\x00' # number of additionals
        )

        Bytes which are expected when encoding an instance constructed using
        C{kwargs} and which are expected to result in an identical instance when
        decoded.

        @return: The L{bytes} of a wire encoded message.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/names/test/test_dns.py