def test_invalid_class():
    ppn = Perceptron(epochs=40, eta=0.01, random_seed=1)
    try:
        ppn.fit(X, y2)  # -2, 1 class
        assert(1 == 2)
    except __HOLE__:
        pass
dataset/ETHPy150Open rasbt/mlxtend/mlxtend/classifier/tests/test_perceptron.py/test_invalid_class