Function no_key

pub fn no_key() -> String

What to tell somebody who has no application key.

Named separately from crate::acoustid::no_key rather than shared: the two services, the two registration pages and the two variables are not the same fact stated twice, and a reader following one must not be sent to register at the other’s address by an error message that forgot which it was talking about.

States only the key itself, never who is affected: --portraits can fall back to Wikidata and --logos cannot, so which artists a missing key leaves untouched is a different sentence for each — one this function does not know and must not guess at — and each pass says it in the line before this one is printed.