docs: def FirstSlotSlicer(primary_query, secondary_query, limit=30):  # noqa
      """
      Inject the first object from a queryset into the first position of a reading list.
  
      :param primary_queryset: djes.LazySearch object. Default queryset for reading list.
      :param secondary_queryset: djes.LazySearch object. first result leads the reading_list.
      :return list: mixed reading list.
      """
      reading_list = SearchSlicer(limit=limit)
      reading_list.register_queryset(primary_query)
      reading_list.register_queryset(secondary_query, validator=lambda x: bool(x == 0))
      return reading_list