{"ast_node_type":"variable","tokens":[{"end":80,"kind":"keyword","start":0,"text":"let"}]}
        let header = self.lower_fn_header(sig.header, hir::Safety::Safe, attrs);
    ) -> (&'hir hir::Generics<'hir>, hir::FnSig<'hir>) {
        let itctx = ImplTraitContext::Universal;