{"ast_node_type":"other","tokens":[{"end":72,"kind":"keyword","start":0,"text":"Some(codegen_call_argument_operand(fx,"}]}
                Some(codegen_call_argument_operand(fx, &self_arg.node)),
            [self_arg, pack_arg] => (
                codegen_call_argument_operand(fx, &pack_arg.node),