How to use the gita.common.get_config_dir function in gita

def get_info_items() -> Tuple[Dict[str, Callable[[str], str]], List[str]]:
    """
    Return the available information items for display in the `gita ll`
    sub-command, and the ones to be displayed.
    It loads custom information functions and configuration if they exist.
    """
    # default settings
    info_items = {'branch': get_repo_status,
            'commit_msg': get_commit_msg,
            'path': get_path, }
    display_items = ['branch', 'commit_msg']

    # custom settings
    root = common.get_config_dir()
    src_fname = os.path.join(root, 'extra_repo_info.py')
    yml_fname = os.path.join(root, 'info.yml')
    if os.path.isfile(src_fname):
        sys.path.append(root)
        from extra_repo_info import extra_info_items
        info_items.update(extra_info_items)
    if os.path.isfile(yml_fname):
        with open(yml_fname, 'r') as stream:
            display_items = yaml.load(stream, Loader=yaml.FullLoader)
        display_items = [x for x in display_items if x in info_items]
    return info_items, display_items