{"ast_node_type":"variable","tokens":[{"end":90,"kind":"keyword","start":0,"text":"let"}]}
                let key = ty::OpaqueTypeKey { def_id: local_def_id, args: alias_ty.args };
            if let Some(local_def_id) = alias_ty.def_id.as_local() {
                if let Some(ty) = cx.reveal_opaque_key(key) {