How to use the autogluon.utils.tabular.utils.savers.save_pkl.save function in autogluon

def save(self):
        save_pkl.save(path=self.path + self.trainer_file_name, object=self)

directory (str): if unspecified, use self.path as directory
            return_name (bool): return the file-names corresponding to this save as tuple (model_obj_file, net_params_file)
        """
        if directory is not None:
            path = directory + file_prefix
        else:
            path = self.path + file_prefix
        params_filepath = path + self.params_file_name
        modelobj_filepath = path + self.model_file_name
        if self.model is not None:
            self.model.save_parameters(params_filepath)
        temp_model = self.model
        temp_sw = self.summary_writer
        self.model = None
        self.summary_writer = None
        save_pkl.save(path=modelobj_filepath, object=self, verbose=verbose)
        self.model = temp_model
        self.summary_writer = temp_sw
        if return_name:
            return (modelobj_filepath, params_filepath)

def _callback(env):
        if ((env.iteration - offset) % interval == 0) & (env.iteration != 0):
            save_pkl.save(path=path, object=env.model)
            save_pointer.save(path=latest_model_checkpoint, content_path=path)
    _callback.before_iteration = True

def save(self, file_prefix=""):
        """ Additional naming changes will be appended to end of file_prefix (must contain full absolute path) """
        dataobj_file = file_prefix + self.DATAOBJ_SUFFIX
        datalist_file = file_prefix + self.DATAVALUES_SUFFIX
        data_list = self.dataset._data
        self.dataset = None # Avoid pickling these
        self.dataloader = None
        save_pkl.save(path=dataobj_file, object=self)
        mx.nd.save(datalist_file, data_list)
        logger.debug("TabularNN Dataset saved to files: \n %s \n %s" % (dataobj_file, datalist_file))

def save(self, file_prefix ="", directory = None, return_filename=False, verbose=True):
        if directory is None:
            directory = self.path
        file_name = directory + file_prefix + self.model_file_name
        save_pkl.save(path=file_name, object=self, verbose=verbose)
        if return_filename:
            return file_name

if directory is None:
            directory = self.path
        directory = directory + file_prefix

        if save_children:
            model_names = []
            for child in self.models:
                child = self.load_child(child)
                child.path = self.create_contexts(self.path + child.name + '/')
                child.save(verbose=False)
                model_names.append(child.name)
            self.models = model_names

        file_name = directory + self.model_file_name

        save_pkl.save(path=file_name, object=self, verbose=verbose)
        if return_filename:
            return file_name

def save_artifacts(predictor, leaderboard, config):
    artifacts = config.framework_params.get('_save_artifacts', ['leaderboard'])
    try:
        models_dir = output_subdir("models", config)
        shutil.rmtree(os.path.join(models_dir, "utils"), ignore_errors=True)

        if 'leaderboard' in artifacts:
            save_pd.save(path=os.path.join(models_dir, "leaderboard.csv"), df=leaderboard)

        if 'info' in artifacts:
            ag_info = predictor.info()
            info_dir = output_subdir("info", config)
            save_pkl.save(path=os.path.join(info_dir, "info.pkl"), object=ag_info)

        if 'models' in artifacts:
            utils.zip_path(models_dir,
                           os.path.join(models_dir, "models.zip"))

        def delete(path, isdir):
            if isdir:
                shutil.rmtree(path, ignore_errors=True)
            elif os.path.splitext(path)[1] == '.pkl':
                os.remove(path)
        utils.walk_apply(models_dir, delete, max_depth=0)

    except Exception:
        log.warning("Error when saving artifacts.", exc_info=True)