{"ast_node_type":"function","tokens":[{"end":65,"kind":"keyword","start":0,"text":"let"}]}
            let is_const_fn = tcx.is_const_fn(def_id.to_def_id())
            // The function has a `const` modifier or is in a `const trait`.
                || tcx.is_const_default_method(def_id.to_def_id());