Oh yeah thank you, It seems developed. But I’m still getting problem in hyperparameter_search method. I defined my backend parameter to ‘optuna’ but the error said: You picked the optuna backend, but it is not installed. Use pip install optuna., though I’ve already pip-installed it before the hyperparameter_search code line. The case was same when I defined the backend parameter into ‘ray’. Have I make a mistake? I run my code in Google Colab by the way.