python
class Animal:
def speak(self):
pass
class Dog(Animal):
def speak(self):
class Cat(Animal):
def speak(self):
class AnimalFactory:
def create_animal(self, animal_type):
if animal_type == "dog":
return Dog()
elif animal_type == "cat":
return Cat()
else:
factory = AnimalFactory()
animal = factory.create_animal("dog")
