{"ast_node_type":"other","tokens":[{"end":46,"kind":"keyword","start":0,"text":"ty::Coroutine(def_id,"}]}
                ty::Coroutine(def_id, ..) => {
                ty::Closure(..) | ty::CoroutineClosure(..) => Some(MustUsePath::Closure(span)),
                    // async fn should be treated as "implementor of `Future`"