How to use the pygelf.gelf.pack function in pygelf

def test_pack(compress):
    message = {'version': '1.1', 'short_message': 'test pack', 'foo': _ObjWithStr()}
    expected = json.loads(json.dumps(message, default=str))
    packed_message = gelf.pack(message, compress, default=str)
    unpacked_message = zlib.decompress(packed_message) if compress else packed_message
    unpacked_message = json.loads(unpacked_message.decode('utf-8'))
    assert expected == unpacked_message

def makePickle(self, record):
        message = gelf.make(record, self.debug, self.additional_fields)
        packed = gelf.pack(message)

        """ if you send the message over tcp, it should always be null terminated or the input will reject it """
        return packed + b'\x00'

def convert_record_to_gelf(self, record):
        return gelf.pack(
            gelf.make(record, self.domain, self.debug, self.version, self.additional_fields, self.include_extra_fields),
            self.compress, self.json_default
        )