{"ast_node_type":"variable","tokens":[{"end":39,"kind":"keyword","start":0,"text":"let"}]}
    let sp = cx.with_def_site_ctxt(sp);
) -> MacroExpanderResult<'static> {
    let ExpandResult::Ready(mac) = get_single_str_spanned_from_tts(cx, sp, tts, "include_bytes!")