{"ast_node_type":"function","tokens":[{"end":74,"kind":"keyword","start":0,"text":"pub"}]}
    pub fn opt_associated_item(self, def_id: DefId) -> Option<AssocItem> {
        if let DefKind::AssocConst | DefKind::AssocFn | DefKind::AssocTy = self.def_kind(def_id) {