def clean_semver(cls, version_spec):
        return re.sub(r"([<>=~])\s+?v?", "\\1", version_spec, re.IGNORECASE)
def index(self, request):
        queryset = Condition.objects.select_related('source', 'target_option')
        serializer = ConditionIndexSerializer(queryset, many=True)
        return Response(serializer.data)