Function find_in_prelude 

fn find_in_prelude(
    db: &dyn SourceDatabase,
    local_def_map: &DefMap,
    item: ItemInNs,
    from: ModuleIdLt<'_>,
) -> Option<Choice>

Returns single-segment path (i.e. without any prefix) if item is found in prelude and its name doesn’t clash in current scope.