/**
* Creates a tz database time-zone code.
*
* <p>Examples might be {@code Europe/London} or {@code Asia/Hong_Kong}.
*
* @param zone the time-zone, not null
* @return the region identifier, not null
*/
public static ExternalId timeZoneRegionId(TimeZone zone) {
ArgumentChecker.notNull(zone, "zone");
return ExternalId.of(TZDB_TIME_ZONE, zone.getID());
}
