{"ast_node_type":"variable","tokens":[{"end":17,"kind":"keyword","start":0,"text":"let"}]}
    let adt_env =
    let impl_adt_ty = Ty::new_adt(tcx, tcx.adt_def(adt_def_id), adt_to_impl_args);
        ty::EarlyBinder::bind(tcx.param_env(adt_def_id)).instantiate(tcx, adt_to_impl_args);