继承
子类继承父类
class Animal(object):
def run(self):
print('Animal is running...')
class Dog(Animal):
# 使程序结构完成，不报错
pass
dog=Dog()
dog.run()
继承
子类继承父类，并覆盖父类
class Animal(object):
def run(self):
print('Animal is running...')
class Cat(Animal):
# 子类有和父类一样的方法，子类覆盖父类
def run(self):
print('cat is running')
cat=Cat()
cat.run()
继承且覆盖
多态
多态
class Animal(object):
def run(self):
print('Animal is running...')
class Cat (Animal):
# 子类有和父类一样的方法，子类覆盖父类
def run(self):
print('cat is running..')
class Dog(Animal):
# 使程序结构完成，不报错 pass
def run(self):
print('dog is running...')
def run_twice(animal):
animal.run()
animal.run()
run_twice(Animal())
动态语言
class Timer(object):
def run(self):
print('start...')
def run_twice(animal):
animal.run()
animal.run()
run_twice(Timer())
