def on_cleanup_error(function, path, excinfo):
                click.secho("warning: failed to remove file or directory: {}\n"
                            "please delete it manually.".format(path),
                            fg="red")
def index(self, request):
        queryset = Condition.objects.select_related('source', 'target_option')
        serializer = ConditionIndexSerializer(queryset, many=True)
        return Response(serializer.data)