def __repr__(self):
        return "<Requirement(package={package}, version='{version}')>".format(
            package=self.package, version=self.version)
def export(self, request):
        serializer = ConditionExportSerializer(self.get_queryset(), many=True)
        xml = ConditionRenderer().render(serializer.data)
        return XMLResponse(xml, name='conditions')