def METHOD_NAME(args):
    if args.locale:
        update_locales(args.locale, args.region, args.year)
    else:
        # Enumerate all holiday files in the current directory.
        locales = []
        re_holiday_file = re.compile(r"/holidays.([a-z]{2}-[A-Z]{2}$)")
        for file in enumerate('.'):
            result = re_holiday_file.search(file)
            if result:
                # Extract the locale name.
                locales.append(result.group(1))
        update_locales(locales, args.region, args.year)