docs: def setup_timezone(timezone: str) -> None:
      """Shortcut helper to configure timezone for backend application.
  
      :param timezone: Timezone to use, e.g. "UTC", "Europe/Kiev".
      """
      if timezone and hasattr(time, 'tzset'):
          tz_root = '/usr/share/zoneinfo'
          tz_filename = os.path.join(tz_root, *(timezone.split('/')))
  
          if os.path.exists(tz_root) and not os.path.exists(tz_filename):
              raise ValueError('Incorrect timezone value: {0}'.format(timezone))
  
          os.environ['TZ'] = timezone
          time.tzset()