old_contents: class Song(object):
  
  	def __init__(self, title, artist, album):
  		self.title = title
  		self.artist = artist
  		self.album = album
  
  	def __repr__(self):
  		return '{} by {} ({})'.format(self.title, self.artist, self.album or 'No Album')
  
new_contents: class Song(object):
  
      def __init__(self, title, artist, album):
          self.title = title
          self.artist = artist
          self.album = album
  
      def __repr__(self):
          return '{} by {} ({})'.format(self.title, self.artist, self.album or 'No Album')
  
      def __eq__(self, other): 
          return self.__dict__ == other.__dict__
subject: Add equality to song type