How to use the msgpack.pack function in msgpack

def test_unpack_tell():
    stream = io.BytesIO()
    messages = [2 ** i - 1 for i in range(65)]
    messages += [-(2 ** i) for i in range(1, 64)]
    messages += [
        b"hello",
        b"hello" * 1000,
        list(range(20)),
        {i: bytes(i) * i for i in range(10)},
        {i: bytes(i) * i for i in range(32)},
    ]
    offsets = []
    for m in messages:
        pack(m, stream)
        offsets.append(stream.tell())
    stream.seek(0)
    unpacker = Unpacker(stream, strict_map_key=False)
    for m, o in zip(messages, offsets):
        m2 = next(unpacker)
        assert m == m2
        assert o == unpacker.tell()

for typename in typelist:
            type_def = schema[typename]
            msgpack.pack(len(type_def), output, use_bin_type=True)

            layer_cols = []
            for k, v in type_def.items():
                layer_cols.append(k)

                msgpack.pack(k, output, use_bin_type=True)
                if isinstance(v, str):
                    msgpack.pack(False, output)
                    msgpack.pack(v, output, use_bin_type=True)
                elif isinstance(v, dict):
                    msgpack.pack(True, output)
                    msgpack.pack(v["type"], output, use_bin_type=True)
                    msgpack.pack(v["args"], output, use_bin_type=True)
                else:
                    raise NotImplementedError()

            types2columns[typename] = layer_cols

        out_texts = BytesIO()

        # 4. Write Texts
        msgpack.pack(texts, out_texts, use_bin_type=True)

        msgpack.pack(out_texts.tell(), output)
        output.write(out_texts.getbuffer()[0:out_texts.tell()])

        # 5. Write Type data
        out_types = BytesIO()
        for typename in typelist:

def dump_key_data(key_data, file):
    import msgpack
    dump_data = (key_data[0].id, tuple(ki.dump() for ki in key_data[1]))
    msgpack.pack(dump_data, file)

def save_object(object_, file_path):

    def ndarrray_to_list(o, _warned=[False]): # Use a mutlable default arg to hold a fn interal temp var.
        if isinstance(o, np.ndarray):
            if not _warned[0]:
                logger.warning("numpy array {} will be serialized as list".format(o))
                _warned[0] = True
            return o.tolist()

    file_path = os.path.expanduser(file_path)
    with open(file_path, 'wb') as fh:
        msgpack.pack(object_, fh, use_bin_type=True,default=ndarrray_to_list)

def send_msg(self, msg_dict):
        """"Messages are delimited by msgapck itself, no need for Storm
        multilang end line.
        """
        msgpack.pack(msg_dict, self._output_stream)
        self._output_stream.flush()

out_props = BytesIO()

        # TODO: Implement extension handling!
        msgpack.pack(doc.props, out_props)

        msgpack.pack(out_props.tell(), output)
        output.write(out_props.getbuffer()[0:out_props.tell()])

        # 2. Write Inventory of types
        msgpack.pack(typelist, output, use_bin_type=True)
        types2columns = {}

        # 3. Write Schema
        for typename in typelist:
            type_def = schema[typename]
            msgpack.pack(len(type_def), output, use_bin_type=True)

            layer_cols = []
            for k, v in type_def.items():
                layer_cols.append(k)

                msgpack.pack(k, output, use_bin_type=True)
                if isinstance(v, str):
                    msgpack.pack(False, output)
                    msgpack.pack(v, output, use_bin_type=True)
                elif isinstance(v, dict):
                    msgpack.pack(True, output)
                    msgpack.pack(v["type"], output, use_bin_type=True)
                    msgpack.pack(v["args"], output, use_bin_type=True)
                else:
                    raise NotImplementedError()

try:
            with open("secrets/known_searches.msgp", "rb") as f:
                known_searches = msgpack.unpack(f, raw=False)
        except ValueError:
            known_searches = {}
    
    if not uri in known_searches:
        filters = loop.run_until_complete(
            search.adjust_api_and_web_filters("https://allegro.pl" + uri, auth)
        )

        known_searches[uri] = filters

        if settings["search"]["cache_file"]:
            with open("secrets/known_searches.msgp", "wb") as f:
                msgpack.pack(known_searches, f)

    result = loop.run_until_complete(
                search.search(known_searches[uri]["api"], auth,
                              limit=settings["search"]["search_results_limit"])
            )

    offers = []
    if not settings["search"]["only_regular_offers"]:
        for offer in result["items"]["promoted"]:
            offers.append(offer)
    for offer in result["items"]["regular"]:
        offers.append(offer)

    rss_feed = []
    for offer in offers:
        description = description_builder(uri, known_searches, offer)

def write_to(self, stream):
        return msgpack.pack(self.pack(self.sender), stream)

msgpack.pack(typelist, output, use_bin_type=True)
        types2columns = {}

        # 3. Write Schema
        for typename in typelist:
            type_def = schema[typename]
            msgpack.pack(len(type_def), output, use_bin_type=True)

            layer_cols = []
            for k, v in type_def.items():
                layer_cols.append(k)

                msgpack.pack(k, output, use_bin_type=True)
                if isinstance(v, str):
                    msgpack.pack(False, output)
                    msgpack.pack(v, output, use_bin_type=True)
                elif isinstance(v, dict):
                    msgpack.pack(True, output)
                    msgpack.pack(v["type"], output, use_bin_type=True)
                    msgpack.pack(v["args"], output, use_bin_type=True)
                else:
                    raise NotImplementedError()

            types2columns[typename] = layer_cols

        out_texts = BytesIO()

        # 4. Write Texts
        msgpack.pack(texts, out_texts, use_bin_type=True)

        msgpack.pack(out_texts.tell(), output)
        output.write(out_texts.getbuffer()[0:out_texts.tell()])