面向对象的问题，不难，只是我不会

Question

面相对象的问题，比较简单吧，只是我不会啊，难过，请来个厉害的人帮助我一下吧！！

Answer 1

代码如下：

class Bucket:
    left_water = 1000


class Outer:
    def __init__(self, bucket):
        self.bucket = bucket

    def pour_out(self, size):
        # 出水
        self.bucket.left_water -= size


class Inter:
    def __init__(self, bucket):
        self.bucket = bucket

    def pour_in(self, size):
        # 进水
        self.bucket.left_water += size


if __name__ == '__main__':
    bucket = Bucket()
    outer = Outer(bucket)
    inter = Inter(bucket)
    i = 0
    while bucket.left_water > 0:
        outer.pour_out(55)
        inter.pour_in(22)
        i += 1
    print("需要", i, "秒放完水")