class Animal(object):
    def run(self):
        print('Animal is running...')

    def jump(self):
        print('Animal is jumpping....')

    def __run(self):
        print('I am a private method.')

class Dog(Animal):
    def run(self):
        print('Dog is running...')

class Cat(Animal):
    def run(self):
        print('Cat is running...')

class Bird(Animal):
    def run(self):
        print('Bird is flying the sky...')

def run_two_times(animal):
    animal.run()
    animal.run()

run_two_times(Bird())