message: Add one more
diff: @@ -851,7 +851,8 @@ class Layer(trackable.Trackable):
  # We will not raise this error in the foll use case for the sake of
  # consistency as name in provided in the metric constructor.
  - # model.add_metric(metrics.Mean(name='my_metric')(outputs))
  + # mean = metrics.Mean(name='my_metric')
  + # model.add_metric(mean(outputs))
  raise ValueError('Please provide a name for your metric like '
  '`self.add_metric(tf.reduce_sum(inputs), '
  'name=\'mean_activation\', aggregation=\'mean\')`')
  