def METHOD_NAME(self, request, *args, **kwargs):
    if 'export' in request.GET:
        content_type = ContentType.objects.get_for_model(self.get_serializer_class().Meta.model)
        et = ExportTemplate.objects.filter(content_types=content_type, name=request.GET['export']).first()
        if et is None:
            raise Http404
        queryset = self.filter_queryset(self.get_queryset())
        return et.render_to_response(queryset)
    return super().METHOD_NAME(request, *args, **kwargs)