回归评估-均方误差

def solve():
    from sklearn.metrics import mean_squared_error
    y_true = [3, 5, 7, 9]
    y_pred = [2.5, 5.5, 6.5, 9.5]
    mse = mean_squared_error(y_true, y_pred)
    print('MSE:', round(mse, 4))