docs: def get_results(self, request):
          """
          Temporarily decreases the `level` attribute of all search results in
          order to prevent indendation when displaying them.
          """
          super(MediaTreeChangeList, self).get_results(request)
          try:
              reduce_levels = abs(int(get_request_attr(request, 'reduce_levels', 0)))
          except TypeError:
              reduce_levels = 0
          is_filtered = self.is_filtered(request)
          if is_filtered or reduce_levels:
              for item in self.result_list:
                  item.prevent_save()
                  item.actual_level = item.level
                  if is_filtered:
                      item.reduce_levels = item.level
                      item.level = 0
                  else:
                      item.reduce_levels = reduce_levels
                      item.level = max(0, item.level - reduce_levels)