def get_next_id(self):
        try:
            query = {'_id': 'last_id'}
            update = {'$inc': {'id': 1}}
            fn = self.db.internal.find_and_modify
            row = fn(query, update, upsert=True, new=True)
        except Exception as e:
            raise DatabaseException(e)
        return row['id']
def setLDAPDirectory(self, directory=None):
        if directory is None:
                self.directory = []
        else:
            try:
                with open(DIRECTORY, 'w+') as f:
                    f.write(str(directory))
                    self.directory = directory
            except OSError as e:
                raise