code: public static Region getInstance(String id) {
  
          if ( id == null ) {
              throw new NullPointerException();
          }
  
          loadRegionData();
  
          Region r = regionIDMap.get(id);
  
          if ( r == null ) {
              r = regionAliases.get(id);
          }
  
          if ( r == null ) {
              throw new IllegalArgumentException("Unknown region id: " + id);         
          }
  
          if ( r.type == RegionType.DEPRECATED && r.preferredValues.size() == 1) {
              r = r.preferredValues.get(0);
          }
  
          return r;
      }
docs: Returns a Region using the given region ID.  The region ID can be either a 2-letter ISO code,
  3-letter ISO code,  UNM.49 numeric code, or other valid Unicode Region Code as defined by the CLDR.
  @param id The id of the region to be retrieved.
  @return The corresponding region.
  @throws NullPointerException if the supplied id is null.
  @throws IllegalArgumentException if the supplied ID cannot be canonicalized to a Region ID that is known by ICU.