How to use the msgpack.ext.Timestamp function in msgpack

def from_unix(unix_sec):
        """Create a Timestamp from posix timestamp in seconds.

        :param unix_float: Posix timestamp in seconds.
        :type unix_float: int or float.
        """
        seconds = int(unix_sec // 1)
        nanoseconds = int((unix_sec % 1) * 10 ** 9)
        return Timestamp(seconds, nanoseconds)

def test_pack_datetime():
    t = Timestamp(42, 14000)
    dt = t.to_datetime()
    assert dt == datetime.datetime(1970, 1, 1, 0, 0, 42, 14, tzinfo=_utc)

    packed = msgpack.packb(dt, datetime=True)
    packed2 = msgpack.packb(t)
    assert packed == packed2

    unpacked = msgpack.unpackb(packed)
    print(packed, unpacked)
    assert unpacked == t

    unpacked = msgpack.unpackb(packed, timestamp=3)
    assert unpacked == dt

    x = []
    packed = msgpack.packb(dt, datetime=False, default=x.append)

def test_timestamp():
    # timestamp32
    ts = Timestamp(2 ** 32 - 1)
    assert ts.to_bytes() == b"\xff\xff\xff\xff"
    packed = msgpack.packb(ts)
    assert packed == b"\xd6\xff" + ts.to_bytes()
    unpacked = msgpack.unpackb(packed)
    assert ts == unpacked
    assert ts.seconds == 2 ** 32 - 1 and ts.nanoseconds == 0

    # timestamp64
    ts = Timestamp(2 ** 34 - 1, 999999999)
    assert ts.to_bytes() == b"\xee\x6b\x27\xff\xff\xff\xff\xff"
    packed = msgpack.packb(ts)
    assert packed == b"\xd7\xff" + ts.to_bytes()
    unpacked = msgpack.unpackb(packed)
    assert ts == unpacked
    assert ts.seconds == 2 ** 34 - 1 and ts.nanoseconds == 999999999

def test_timestamp_from():
    t = Timestamp(42, 14000)
    assert Timestamp.from_unix(42.000014) == t
    assert Timestamp.from_unix_nano(42000014000) == t

def test_timestamp():
    # timestamp32
    ts = Timestamp(2 ** 32 - 1)
    assert ts.to_bytes() == b"\xff\xff\xff\xff"
    packed = msgpack.packb(ts)
    assert packed == b"\xd6\xff" + ts.to_bytes()
    unpacked = msgpack.unpackb(packed)
    assert ts == unpacked
    assert ts.seconds == 2 ** 32 - 1 and ts.nanoseconds == 0

    # timestamp64
    ts = Timestamp(2 ** 34 - 1, 999999999)
    assert ts.to_bytes() == b"\xee\x6b\x27\xff\xff\xff\xff\xff"
    packed = msgpack.packb(ts)
    assert packed == b"\xd7\xff" + ts.to_bytes()
    unpacked = msgpack.unpackb(packed)
    assert ts == unpacked
    assert ts.seconds == 2 ** 34 - 1 and ts.nanoseconds == 999999999

    # timestamp96
    ts = Timestamp(2 ** 63 - 1, 999999999)
    assert ts.to_bytes() == b"\x3b\x9a\xc9\xff\x7f\xff\xff\xff\xff\xff\xff\xff"
    packed = msgpack.packb(ts)
    assert packed == b"\xc7\x0c\xff" + ts.to_bytes()
    unpacked = msgpack.unpackb(packed)
    assert ts == unpacked
    assert ts.seconds == 2 ** 63 - 1 and ts.nanoseconds == 999999999

def test_timestamp_to():
    t = Timestamp(42, 14000)
    assert t.to_unix() == 42.000014
    assert t.to_unix_nano() == 42000014000

def from_unix_nano(unix_ns):
        """Create a Timestamp from posix timestamp in nanoseconds.

        :param int unix_ns: Posix timestamp in nanoseconds.
        :rtype: Timestamp
        """
        return Timestamp(*divmod(unix_ns, 10 ** 9))

self._buffer.write(struct.pack("b", code))
                self._buffer.write(data)
                return
            if check(obj, list_types):
                n = len(obj)
                self._pack_array_header(n)
                for i in xrange(n):
                    self._pack(obj[i], nest_limit - 1)
                return
            if check(obj, dict):
                return self._pack_map_pairs(
                    len(obj), dict_iteritems(obj), nest_limit - 1
                )

            if self._datetime and check(obj, _DateTime):
                obj = Timestamp.from_datetime(obj)
                default_used = 1
                continue

            if not default_used and self._default is not None:
                obj = self._default(obj)
                default_used = 1
                continue
            raise TypeError("Cannot serialize %r" % (obj,))

n = len(obj)
                if n >= 2 ** 32:
                    raise ValueError("String is too large")
                self._pack_raw_header(n)
                return self._buffer.write(obj)
            if check(obj, memoryview):
                n = len(obj) * obj.itemsize
                if n >= 2 ** 32:
                    raise ValueError("Memoryview is too large")
                self._pack_bin_header(n)
                return self._buffer.write(obj)
            if check(obj, float):
                if self._use_float:
                    return self._buffer.write(struct.pack(">Bf", 0xCA, obj))
                return self._buffer.write(struct.pack(">Bd", 0xCB, obj))
            if check(obj, (ExtType, Timestamp)):
                if check(obj, Timestamp):
                    code = -1
                    data = obj.to_bytes()
                else:
                    code = obj.code
                    data = obj.data
                assert isinstance(code, int)
                assert isinstance(data, bytes)
                L = len(data)
                if L == 1:
                    self._buffer.write(b"\xd4")
                elif L == 2:
                    self._buffer.write(b"\xd5")
                elif L == 4:
                    self._buffer.write(b"\xd6")
                elif L == 8: