def METHOD_NAME(self, data_parallel_size):
    for idx, item in enumerate(self.opt_list):
        if item[0] == "parallel_mode":
            if item[1] is not None:
                # item[1] is tuple(list(name, size), Oneof(None, rank_list), Optional(bool))
                support_multi_parallel_instance = item[1][2] if len(item[1]) > 2 else False
                if support_multi_parallel_instance:
                    break
                pg_list = []
                for name, size in item[1][0]:
                    if name == "data":
                        pg_list.append((name, data_parallel_size))
                    else:
                        pg_list.append((name, size))
                new_config = (pg_list, item[1][1])
                self.opt_list[idx] = (item[0], new_config, False)
            else:
                self.opt_list[idx] = (item[0], ([("data", data_parallel_size)], None), False)
            break