compiler/rustc_baked_icu_data/src/data/fallback/supplement/co_v1/mod.rs

// @generated
type DataStruct = < :: icu_provider_adapters :: fallback :: provider :: CollationFallbackSupplementV1Marker as :: icu_provider :: DataMarker > :: Yokeable ;
pub fn lookup(locale: &icu_provider::DataLocale) -> Option<&'static DataStruct> {
    locale.is_empty().then(|| &UND)
}
static UND: DataStruct = include!("und.rs.data");