Clarifying the 'market' field in API requests.

[mkspainhour]

The 'market' field uses the ISO 3166-1 alpha-2 standard to denote a listening territory in request. Spotify lists Kosovo as a supported territory, but as far as I can tell, Kosovo has no formally assigned ISO 3166-1 alpha-2 code. "XK" seems to be the informally agreed-upon identifier until one is officially designated, and the API seems to agree.

• In the event that Kosovo is assigned a formal country code that is not "XK", how might the API fold such a change in?
• Is there a written list of all API-supported ISO 3166-1 alpha-2 codes? I ended up hand-transcribing them for myself based on the supported territories page, but a copy-paste-able list would have been handy.
• In the future, what would be the best way for someone using the API to know that Spotify has expanded to an additional market?

Thanks for any info any one is able to offer!