code: def register_options(this_class, argparser):
          
          default_path = this_class.rc_file_basename
          default_basename = os.path.basename(default_path)
          argparser.add_argument('-c', "--config-file",
                                 default=default_path,
                                 help=("Configuration file to use for lookups " +
                                       "(replaces DEFAULT=%s " % (default_path) +
                                       "but not ~/%s)" % (default_basename)))
docs: This class method is called so that ConfigFromFile can tell the
          command-line parser to register the options specific to the class.
  
          :param this_class: Not used (required by @classmethod interface)
          :param argparser: The argparser instance being prepared for use.