message: BUG: log_cosh alias missing results in round-trip serialization failure
diff: @@ -3402,6 +3402,7 @@ mae = MAE = mean_absolute_error
  mape = MAPE = mean_absolute_percentage_error
  msle = MSLE = mean_squared_logarithmic_error
  cosine_similarity = cosine_proximity
  +log_cosh = logcosh
  def clone_metric(metric):
  