docs: public void writeTo(String zoneID, DataOutput out) throws IOException {
          // pass false so zone id is not written out
          DateTimeZone zone = toDateTimeZone(zoneID, false);
  
          if (zone instanceof FixedDateTimeZone) {
              out.writeByte('F'); // 'F' for fixed
              out.writeUTF(zone.getNameKey(0));
              writeMillis(out, zone.getOffset(0));
              writeMillis(out, zone.getStandardOffset(0));
          } else {
              if (zone instanceof CachedDateTimeZone) {
                  out.writeByte('C'); // 'C' for cached, precalculated
                  zone = ((CachedDateTimeZone)zone).getUncachedZone();
              } else {
                  out.writeByte('P'); // 'P' for precalculated, uncached
              }
              ((PrecalculatedZone)zone).writeTo(out);
          }
      }