code: def related_to(self, entry, live_only=False):
          
          filters = {'tag__in': entry.tags}
  
          if live_only:
              filters.update({'entry__live': True})
  
          return self.filter(**filters).exclude(entry=entry)
docs: Returns queryset of Entry instances related to specified
          Entry instance.
  
          :param entry: the Entry instance.
          :param live_only: flag to include only "live" entries.
          :rtype: django.db.models.query.QuerySet.