{"ast_node_type":"variable","tokens":[{"end":54,"kind":"keyword","start":0,"text":"let"}]}
            let abi = tcx.hir_get_foreign_abi(hir_id);
        ForeignItem(&hir::ForeignItem { kind: ForeignItemKind::Fn(sig, _, _), .. }) => {
            compute_sig_of_foreign_fn_decl(tcx, def_id, sig.decl, abi, sig.header.safety())