小编Ily*_*rov的帖子

class Song:
    def __init__(self, name):
        self.name = name
        self.next = None

    def next_song(self, song):
        self.next = song 

    def is_repeating_playlist(self):
        """
        :returns: (bool) True if the playlist is repeating, False if not.
        """
        return None

first = Song("Hello")
second = Song("Eye of the tiger")

first.next_song(second);
second.next_song(first);