input: 
  class Song:
      def __init__(self, title, artist):
          self.title = title
          self.artist = artist
    
      def __str__(self):
          return f'Title: {self.title}\nArtist: {self.artist}'
      
      def __eq__(self, other):
          return self.artist == other.artist and self.title == other.title
  
      def length(self):
          return len(self.title)
  
  # Example:
  # song1 = Song("Bohemian Rhapsody", "Queen")
  # song2 = Song("Bohemian Rhapsody", "Queen")
  # print(str(song1))  # Output: Title: Bohemian Rhapsody
                      #          Artist: Queen
  # print(song1 == song2)  # Output: True
  # print(song1.length())  # Output: 17
  
output:     
      def __lt__(self, other):
          if self.artist == other.artist:
              return self.title < other.title
          return self.artist < other.artist
  
      def __hash__(self):
          return hash((self.title, self.artist))
  