{"ast_node_type":"function","tokens":[{"end":65,"kind":"keyword","start":0,"text":"fn"}]}
    fn visit_foreign_item(&mut self, i: &'ast ast::ForeignItem) {
impl<'ast> visit::Visitor<'ast> for WeakLangItemVisitor<'_, '_> {
        if let Some((lang_item, _)) = lang_items::extract(&i.attrs) {