id property
The CLDR 2-letter representation of a country/region, with the exception of "country calling codes" used for non-geographical entities, such as Universal International Toll Free Number (+800). These are all given the ID "001", since this is the numeric region code for the world according to UN M.49: http://en.wikipedia.org/wiki/UN_M.49
Implementation
@$pb.TagNumber(9)
$core.String get id => $_getSZ(8);