code: def get_compressed_filename(self, filename):
          
          if not os.path.splitext(filename)[1][1:] in self.suffixes_to_compress:
              return False
  
          file_stats = None
          compressed_stats = None
          compressed_filename = '{}.{}'.format(filename, self.suffix)
          try:
              file_stats = os.stat(filename)
              compressed_stats = os.stat(compressed_filename)
          except OSError:  # FileNotFoundError is for Python3 only
              pass
  
          if file_stats and compressed_stats:
              return (compressed_filename
                      if file_stats.st_mtime > compressed_stats.st_mtime
                      else False)
          else:
              return compressed_filename
docs: If the given filename should be compressed, returns the
          compressed filename.
  
          A file can be compressed if:
  
          - It is a whitelisted extension
          - The compressed file does not exist
          - The compressed file exists by is older than the file itself
  
          Otherwise, it returns False.