def is_usable(self):
        raise NotImplementedError(
            "subclasses of BaseDatabaseWrapper may require an is_usable() method")
Returns Uncategorized document type rule (In case it is set in system) or None (In case it is not)
dataset/ETHPy150Open cloudera/hue/desktop/core/ext-py/Django-1.6.10/django/db/backends/__init__.py/BaseDatabaseWrapper.is_usable--crossover with--dataset/ETHPy150Open adlibre/Adlibre-DMS/adlibre_dms/apps/core/models.py/DocumentTypeRuleManager.get_uncategorized