def _last_index(self, s):
        self.set_index(max(0, self._find_one_after_last_labeled_index() - 1))
def export(self, request):
        serializer = ConditionExportSerializer(self.get_queryset(), many=True)
        xml = ConditionRenderer().render(serializer.data)
        return XMLResponse(xml, name='conditions')