[tz] From (ISO3166-1 alpha2 + ISO3166-2) country+region code to timezone?

Hello, How is it possible to get the timezone for a specific datetime and a (ISO3166-1 alpha2, ISO3166-2) pair, i.e. a country code + region code ?  Example: ISO3166 -> TimezoneDE-BE -> Europe/Berlin AU-TAS -> Australia/Hobart or Australia/Tasmania US-NY -> America/NewYork Thank you in advance,Jo PS: I have seen the file "iso3166.tab" but this is only for country codes, i.e. the first part of ISO3166.