docs: def _delete_collection(self, ctx):
          """
          Delete a collection from DB, optionally filtered by ``filter_by``
          """
          assert isinstance(ctx, ResourceQueryContext)
  
          filter_by = ctx.get_filter_by()
          q = self._orm.query(self.model_cls)
  
          if filter_by is not None:
              q = self.to_filter(q, filter_by)
  
          return q.delete()