{"ast_node_type":"other","tokens":[{"end":79,"kind":"keyword","start":0,"text":"hir::ClosureKind::CoroutineClosure(hir::CoroutineDesugaring::Async)"}]}
            hir::ClosureKind::CoroutineClosure(hir::CoroutineDesugaring::Async)
            // guide inference here, since it's beneficial for the user.
                if self.tcx.is_lang_item(def_id, LangItem::FnOnceOutput) =>