from model_utils.managers import SoftDeletableManager, SoftDeletableQuerySet class CustomSoftDeleteQuerySet(SoftDeletableQuerySet): def only_read(self): return self.filter(is_read=True) class CustomSoftDeleteManager(SoftDeletableManager): _queryset_class = CustomSoftDeleteQuerySet def only_read(self): return self.get_queryset().only_read()