上述问题输入输出为>>> vanilla = Cat('Vanilla', 'Minazuki Kashou') >>> isinstance(vanilla, Pet) # check if vanilla is an instance of Pet. True >>> vanilla.talk() Vanilla says meow! >>> vanilla.eat('fish') Vanilla ate a fish! >>> vanilla.lose_life() >>> vanilla.lives 8 >>> vanilla.is_alive True >>> for i in range(8): ... vanilla.lose_life() >>> vanilla.lives 0 >>> vanilla.is_alive False >>> vanilla.lose_life() Vanilla has no more lives to lose.

Sure, here is the modified implementation of the Cat class that meets your requirements:

class Cat(Pet):
    def __init__(self, name, owner, lives=9):
        super().__init__(name, owner)
        self.lives = lives

    def talk(self):
        print(self.name + " says meow!")

    def eat(self, thing):
        super().eat(thing)

    def lose_life(self):
        if self.lives > 0:
            self.lives -= 1
            if self.lives == 0:
                self.is_alive = False
        else:
            print(self.name + " has no more lives to lose.")

Here are the doctests:

>>> vanilla = Cat('Vanilla', 'Minazuki Kashou')
>>> isinstance(vanilla, Pet)
True
>>> vanilla.talk()
Vanilla says meow!
>>> vanilla.eat('fish')
Vanilla ate a fish!
>>> vanilla.lose_life()
>>> vanilla.lives
8
>>> vanilla.is_alive
True
>>> for i in range(8):
...     vanilla.lose_life()
>>> vanilla.lives
0
>>> vanilla.is_alive
False
>>> vanilla.lose_life()
Vanilla has no more lives to lose.

I hope this helps!