def type_and_model_to_query(self, request):
        """
        Return JSON for an individual Model instance

        If the required parameters are wrong, return 400 Bad Request
        If the parameters are correct but there is no data, return empty JSON

        """
        try:
            content_type_id = request.GET["content_type_id"]
            object_id = request.GET["object_id"]
        except KeyError:
            return HttpResponseBadRequest()

        try:
            content_type = ContentType.objects.get(pk=content_type_id)
            model = content_type.model_class()
            result = model.objects.get(pk=object_id)
        except ObjectDoesNotExist:
            data = ""
        else:
            data = '%s: "%d: %s"' % (content_type.model, result.pk, result)

        return JsonResponse({"query": data})
Return JSON for an individual Model instance

        If the required parameters are wrong, return 400 Bad Request
        If the parameters are correct but there is no data, return empty JSON