def get_for_model(self, model):
        """
        Return a QuerySet of only items of a certain type.
        """
        return self.filter(content_type=ContentType.objects.get_for_model(model))
def get_for_model ( self , model ) : return self . filter ( content_type = ContentType . objects . get_for_model ( model ) )
Return a QuerySet of only items of a certain type.