input: Write a function to create a class named Song with two instance variables, title and artist, and three methods, str(), eq(), and length(). The str() method should return a formatted string representing the song's title and artist. The eq() method should compare two Song objects based on their title and artist. The length() method should return the length of the title as an integer.
  
  
  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)
  
  
  assert str(Song('Bohemian Rhapsody', 'Queen')) == 'Title: Bohemian Rhapsody\nArtist: Queen'
  assert Song('Bohemian Rhapsody', 'Queen') == Song('Bohemian Rhapsody', 'Queen')
  assert Song('Bohemian Rhapsody', 'Queen') != Song('Stairway to Heaven', 'Led Zeppelin')
  assert Song('Bohemian Rhapsody', 'Queen').length() == 17
output: 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)