[scikit-learn] help

Dear Sir/Madam, I have stumbled upon a problem while trying to run some old code using skcikit-learn: scores = cross_validation.cross_val_score(model, X, Y, cv = 10, score_func = metrics.mean_squared_error) This line will not run in a program I downloaded, and as I am not yet very familliar with scikit-learn I do not know how I should replace "score_func = metrics.mean_squared_error" to produce the same result as intended by the ones who made the program. Any help is greatly appreciated. Best regards, Alexandra Log