import randomclass PetShop:  """寵物商店"""  def __init__(self, animal_factory=None):    """寵物工廠是我們的抽象工廠。我們可以隨意設置。"""     self.pet_factory = animal_factory  def show_pet(self):    """使用抽象工廠創建并顯示一個寵物"""    pet = self.pet_factory.get_pet()    print("我們有一個可愛的 {}".format(pet))    print("它說 {}".format(pet.speak()))    print("我們還有 {}".format(self.pet_factory.get_food()))# 工廠生產的事物class Dog:  def speak(self):    return "汪"  def __str__(self):    return "Dog"class Cat:  def speak(self):    return "喵"  def __str__(self):    return "Cat"# Factory classesclass DogFactory:  def get_pet(self):    return Dog()  def get_food(self):    return "狗食"class CatFactory:  def get_pet(self):    return Cat()  def get_food(self):    return "貓糧"# 隨機創建合適的工廠def get_factory():  """讓我們動起來！"""  return random.choice([DogFactory, CatFactory])()# 多個工廠顯示寵物if __name__ == "__main__":  for i in range(4):    shop = PetShop(get_factory())    shop.show_pet()    print("=" * 20)