class a(object):

    def __init__(self):

        print("aINIT")

    def a1(self):

        print("a")

class b(a):

    def __init__(self):

        super(b, self).__init__()

        print("bINIT")

    def b1(self):

        print("b")

b().a1()

>>>aINIT

>>>bINIT

>>>a