code: def create_shn (archive, compression, cmd, verbosity, interactive, filenames):
      
      if len(filenames) > 1:
          raise util.PatoolError("multiple filenames for shorten not supported")
      cmdlist = [util.shell_quote(cmd)]
      cmdlist.extend(['-', util.shell_quote(archive), '<',
          util.shell_quote(filenames[0])])
      return (cmdlist, {'shell': True})
docs: Compress a WAV file to a SHN archive.