Use Eurostat LAU2 format (DE prefix for LK/KFS/SK)

[dadosch]

LAU2 - formerly knowns as NUTS4-5: https://ec.europa.eu/eurostat/web/nuts/local-administrative-units
US has FIPS which we could put into a subfolder, as the US region and europe likely don't overlap:
John Hopkins switch to FIPS for the US (NY times uses that as well - linked in the issue below)
CSSEGISandData/COVID-19#1250

Improvement like using ISO-3611-2 are welcome, but it seems to be behind a paywall and I've got no idea how to access / use this in a GPL3 project.

Alternatively check this:
http://www.statoids.com/ihasc.html