{"ast_node_type":"variable","tokens":[{"end":51,"kind":"keyword","start":0,"text":"let"}]}
    let extra_args = fx.tcx.mk_type_list_from_iter(
    let extra_args = &args[fn_sig.inputs().skip_binder().len()..];
        extra_args.iter().map(|op_arg| fx.monomorphize(op_arg.node.ty(fx.mir, fx.tcx))),