code: def change_and_save(self, update_only_changed_fields=False, **changed_fields):
          
          bulk_change_and_save(self, update_only_changed_fields=update_only_changed_fields, **changed_fields)
          return self.filter()
docs: Changes a given `changed_fields` on each object in the queryset, saves objects
          and returns the changed objects in the queryset.