How to use the keymapviz.KEYBOARDS function in keymapviz

def parse_arg():
    keyboards = keymapviz.KEYBOARDS.keys()
    types = list(TYPES.keys())

    desc = 'keymap.c visualizer'
    parser = argparse.ArgumentParser(description=desc,
                                     epilog='Following keyboards are supported.\n * '+'\n * '.join(keyboards),
                                     formatter_class=argparse.RawTextHelpFormatter)

    parser.add_argument('-k', '--keyboard', type=str, choices=keyboards, help='keyboard of keymap.c', metavar='keyboards')
    parser.add_argument('-o', '--output',   type=str, help='output file name("{}" is replaced index)')
    parser.add_argument('-r', '--replace',   action='store_true', help='replace comment block including "[keymapviz]" with ascii art. (make *.bac)')
    parser.add_argument('-t', '--type',     dest='type_', type=str, choices=types, default=types[0], help='type of output(default:ascii)')
    parser.add_argument('-v', '--version',  action='version', version='%(prog)s {}'.format(VERSION))
    parser.add_argument('keymap_c',         type=argparse.FileType('r'), help='keymap.c file name')

    arg = parser.parse_args()