code: def get_album_songs(self, album_id):
          
  
          url = 'http://music.163.com/api/album/{}/'.format(album_id)
          result = self.get_request(url)
  
          songs = result['album']['songs']
          songs = [Song(song['id'], song['name']) for song in songs]
          return songs
docs: Get a album's all songs.
  
          warning: use old api.
          :params album_id: album id.
          :return: a list of Song object.