def search(self, regex):
        try:
            spec = {'$or': [{'data.content'    : {'$regex': regex, '$options': 'im'}},
                            {'data.description': {'$regex': regex, '$options': 'im'}}]}
            fields = {'_id': 0}
            cur = self.db.docs.find(spec, fields)
        except Exception as e:
            raise DatabaseException(e)
        return [Document(**row) for row in cur]
def _model_ready(self, sess):
    """Checks if the model is ready or not.

    Args:
      sess: A `Session`.

    Returns:
      A tuple (is_ready, msg), where is_ready is True if ready and False
      otherwise, and msg is `None` if the model is ready, a `String` with the
      reason why it is not ready otherwise.
    """
    return _ready(self._ready_op, sess, "Model not ready")