How to use the tts.filesystem.FileSystem function in TTS

# set logging
    if args.loglevel:
      logmap={
        'debug':logging.DEBUG,
        'info':logging.INFO,
        'warn':logging.WARN,
        'error':logging.ERROR
       }
      tts.logger().setLevel(logmap[args.loglevel])
    else:
      tts.logger().setLevel(logging.WARN)

    # load filesystem values
    if args.directory:
      self.filesystem = tts.filesystem.FileSystem(os.path.abspath(args.directory))
    else:
      self.filesystem = tts.get_default_fs()

    if (args.parser=='list' or args.parser=='export') and not args.save_type:
      # set default
      args.save_type = tts.SaveType.workshop

    if (args.parser=='config' and args.parser_config=='set' and not args.mod_location and not args.tts_location):
      #parser_config.print_usage()
      parser_config_set.error("At least one of -m or -t is required.")

    rc,message = args.func(args)
    if message:
      print(message)
    sys.exit(rc)

def do_config_validate(self,args):
    fs=tts.filesystem.FileSystem(tts_install_path=self.preferences.TTSLocation)
    if fs.check_dirs():
      return 0,"Configuration validated OK."
    else:
      return 1,"Configuration failed to validate."

def get_default_fs():
  return FileSystem(standard_basepath())

def reload_filesystem(self):
    if self.preferences.locationIsUser:
      self.filesystem=tts.get_default_fs()
    else:
      self.filesystem=tts.filesystem.FileSystem(tts_install_path=self.preferences.TTSLocation)

def export(self,export_filename):
    log=tts.logger()
    log.info("About to export %s to %s" % (self.ident,export_filename))
    zfs = tts.filesystem.FileSystem(base_path="")
    zipComment = {
      "Ver":1,
      "Id":self.ident,
      "Type":self.save_type.name
    }

    # TODO: error checking.
    with zipfile.ZipFile(export_filename,'w') as zf:
      zf.comment=json.dumps(zipComment).encode('utf-8')
      log.debug("Writing {} (base {}) to {}".format(self.filename,os.path.basename(self.filename),zfs.get_path_by_type(os.path.basename(self.filename),self.save_type)))
      zf.write(self.filename,zfs.get_path_by_type(os.path.basename(self.filename),self.save_type))
      for url in self.models:
        log.debug("Writing {} to {}".format(url.location,zfs.get_model_path(os.path.basename(url.location))))
        zf.write(url.location,zfs.get_model_path(os.path.basename(url.location)))
      for url in self.images:
        log.debug("Writing {} to {}".format(url.location,zfs.get_model_path(os.path.basename(url.location))))