Add "EP" to Country column

I’m working at a IP law firm, and it is very helpful that has a country columns.

However, it would be better if “European Union” added to the country column.
Of course, I know that EU is not a country, but it exists separately in the patent field as a “EPO (Euroepan Patent Office)” application.

If EU cannot be added as a country, it would be nice if the user could add a country.