{"ast_node_type":"variable","tokens":[{"end":27,"kind":"keyword","start":0,"text":"let"}]}
        let tcx = self.tcx;
    ) -> ty::EarlyBinder<'tcx, &'tcx [(ty::Clause<'tcx>, Span)]> {
        let item_def_id = tcx.hir_ty_param_owner(def_id);