code: def get_artists_hot_songs(self, artist_id):
          
          url = 'http://music.163.com/api/artist/{}'.format(artist_id)
          result = self.get_request(url)
  
          hot_songs = result['hotSongs']
          songs = [Song(song['id'], song['name']) for song in hot_songs]
          return songs
docs: Get a artist's top50 songs.
  
          warning: use old api.
          :params artist_id: artist id.
          :return: a list of Song object.