It would be nice if reported bugs (json functionality) are fixed in less time.
It is almost 2 years now without any feedback.
There is no way to know json_select_object found the json object or not. Script is useless in big part of the cases.
Try attached script with different artists (Peter Gabriel, Dire Straits, etc). Pay attention to country name column which is set to artist name in many cases.
MusicBrainz__json__Artist.src (2.64 KB)