class SoftDeleteManager(models.Manager):
  def __init__(self, *args, **kwargs):
    self.with_deleted = kwargs.pop('deleted', False)
    super(SoftDeleteManager, self).__init__(*args, **kwargs)

  def _base_queryset(self):
    return super().get_queryset().filter(deleted_at=None)

  def get_queryset(self):
    qs = self._base_queryset()
    if self.with_deleted:
      return qs
    return qs.filter(is_deleted=False)


class SoftDeleteModel(BaseModel):
  class meta:
      abstract = True

  objects = SoftDeleteManager()
  objects_with_deleted = managers.SoftDeleteManager(deleted=True)

  is_deleted = models.BooleanField(null=False, default=False)

  def delete(self):
    self.is_deleted = True
    self.save()

  def restore(self):
    self.is_deleted = False
    self.save()