'Ensure that all appropriate indexes are created that are needed by this modulestore, or raise
an exception if unable to.
This method is intended for use by tests and administrative commands, and not
to be run during server startup.'

def ensure_indexes(self):

    create_collection_index(self.collection, [('_id.tag', pymongo.ASCENDING), ('_id.org', pymongo.ASCENDING), ('_id.course', pymongo.ASCENDING), ('_id.category', pymongo.ASCENDING), ('_id.name', pymongo.ASCENDING), ('_id.revision', pymongo.ASCENDING)], background=True)
    create_collection_index(self.collection, '_id.category', background=True)
    create_collection_index(self.collection, 'definition.children', sparse=True, background=True)
    create_collection_index(self.collection, '_id.revision', background=True)
