code: def normalize(opts):
      
      opts_dict = vars(opts)
      add_is_dir(opts_dict)
      ensure_directories_end_in_separator(opts_dict)
      add_abs_path_directories(opts_dict)
      add_open_close_wrappers(opts_dict)
      add_wrapper_regex(opts_dict)
      return Bunch(opts_dict)
docs: Performs various normalization functions on opts, the provided namespace. It
      is assumed that opts has already been validated with
      anchorhub.validation_opts.validate().
  
      :param opts: a namespace containing options for AnchorHub
      :return: a namespace with the attributes modified