new_contents: class PlaylistNotFoundError(Exception):
      __module__ = Exception.__module__
  
      def __init__(self, message=None):
          super().__init__(message)
  
  
  class AlbumNotFoundError(Exception):
      __module__ = Exception.__module__
  
      def __init__(self, message=None):
          super().__init__(message)
  
  
  class ArtistNotFoundError(Exception):
      __module__ = Exception.__module__
  
      def __init__(self, message=None):
          super().__init__(message)
  
  
  class UserNotFoundError(Exception):
      __module__ = Exception.__module__
  
      def __init__(self, message=None):
          super().__init__(message)
  
  
  class SpotifyPlaylistNotFoundError(PlaylistNotFoundError):
      __module__ = Exception.__module__
  
      def __init__(self, message=None):
          super().__init__(message)
  
  
  class SpotifyAlbumNotFoundError(AlbumNotFoundError):
      __module__ = Exception.__module__
  
      def __init__(self, message=None):
          super().__init__(message)
  
  
  class SpotifyArtistNotFoundError(ArtistNotFoundError):
      __module__ = Exception.__module__
  
      def __init__(self, message=None):
          super().__init__(message)
  
  
  class SpotifyUserNotFoundError(UserNotFoundError):
      __module__ = Exception.__module__
  
      def __init__(self, message=None):
          super().__init__(message)
  
  
subject: Introduce helper exceptions