code: def get_queryset(self):
          
          self.tag = get_tag(self.kwargs['tag'])
          if self.tag is None:
              raise Http404(_('No Tag found matching "%s".') %
                            self.kwargs['tag'])
          return TaggedItem.objects.get_by_model(
              Entry.published.all(), self.tag)
docs: Retrieve the tag by his name and
          build a queryset of his published entries.