docs: def _encode_datetime(name, value, dummy0, dummy1):
      """Encode datetime.datetime."""
      if value.utcoffset() is not None:
          value = value - value.utcoffset()
      millis = int(calendar.timegm(value.timetuple()) * 1000 +
                   value.microsecond / 1000)
      return b"\x09" + name + _PACK_LONG(millis)