def contains(self, item):
check_not_none(item, "<STR_LIT>")<EOL>item_data = self._to_data(item)<EOL>return self._encode_invoke(queue_contains_codec, value=item_data)<EOL>
Determines whether this queue contains the specified item or not.

:param item: (object), the specified item to be searched.
:return: (bool), ``true`` if the specified item exists in this queue, ``false`` otherwise.