sub tidy {
      my ($output) = @_;
      use IPC::Open2;
      open2 *READER, *WRITER, "/usr/bin/tidy -i -w 0 -q -raw 2>/dev/null";
      print WRITER $output;
      close WRITER;
      undef $/;
      $output = <READER>;
      close READER;
      return $output;
  }