from gplearn.fitness import make_fitness, _mean_square_error
// load the boston dataset and randomly permute it
rng = check_random_state(0)
boston = load_boston()
perm = rng.permutation(boston.target.size)
boston.data = boston.data[perm]
boston.target = boston.target[perm]
After Change
// load the breast cancer dataset and randomly permute it
cancer = load_breast_cancer()
perm = check_random_state(0).permutation(cancer.target.size)
cancer.data = cancer.data[perm]
cancer.target = cancer.target[perm]
// load the boston dataset and randomly permute it
