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 batch_norm(inputs, training, data_format, name=''):
  """Performs a batch normalization using a standard set of parameters."""
  # We set fused=True for a significant performance boost. See
  # https://www.tensorflow.org/performance/performance_guide#common_fused_ops
  return tf.compat.v1.layers.batch_normalization(
      inputs=inputs,
      axis=1 if data_format == 'channels_first' else 3,
      momentum=_BATCH_NORM_DECAY,
      epsilon=_BATCH_NORM_EPSILON,
      center=True,
      scale=True,
      training=training,
      fused=True,
      name=name)