{"ast_node_type":"variable","tokens":[{"end":47,"kind":"keyword","start":0,"text":"let"}]}
        let (self_arg, pack_arg) = match args {
    let mut args = if fn_sig.abi() == ExternAbi::RustCall {
            [pack_arg] => (None, codegen_call_argument_operand(fx, &pack_arg.node)),