Redirecionar conforme limite do usuário

gistfile1.py

    def get_form(self, request, obj=None, **kwargs):
        form = super(EstabelecimentoAdmin, self).get_form(request, obj, **kwargs)
        import pdb
        pdb.set_trace()
        try:
            if not request.user.is_superuser:
                if Usuario(user=request.user).get_limit() >= self.model.objects.filter(user=request.user).count() and obj == None:
                    return render_to_response('limit_places.html', {'app_label': 'Limite atingido'})
                form.base_fields['cidade'].queryset = Usuario(user=request.user).get_city()
        except Exception, e:
            print e
        finally:
            return form