Function known_trigram 

pub fn known_trigram(code: &str) -> Option<&'static Trigram>

Available on crate feature language-detection only.

The trigrams of a language’s excerpt, by its code: what music21’s LanguageDetector.trigrams holds.

use music21::features::language::known_trigram;

let french = known_trigram("fr").expect("music21 knows French");
let italian = known_trigram("it").expect("music21 knows Italian");
assert!((0.50..0.55).contains(&french.distance(italian)));
assert!(known_trigram("xx").is_none());