<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def restore_default_settings():
 """ Restore settings to default values. """

    global __DEFAULTS
    __DEFAULTS.CACHE_DIR = defaults.CACHE_DIR
    __DEFAULTS.SET_SEED = defaults.SET_SEED
    __DEFAULTS.SEED = defaults.SEED
    logging.info('Settings reverted to their default values.')