code: def compare_song_collections(src_songs, dst_songs):
  	
  
  	def gather_field_values(song):
  		return tuple((_normalize_metadata(song[field]) for field in _filter_comparison_fields(song)))
  
  	dst_songs_criteria = {gather_field_values(_normalize_song(dst_song)) for dst_song in dst_songs}
  
  	return [src_song for src_song in src_songs if gather_field_values(_normalize_song(src_song)) not in dst_songs_criteria]
docs: Compare two song collections to find missing songs.
  
  	Parameters:
  		src_songs (list): Google Music song dicts or filepaths of local songs.
  
  		dest_songs (list): Google Music song dicts or filepaths of local songs.
  
  	Returns:
  		A list of Google Music song dicts or local song filepaths from source missing in destination.