How to use the gokart.make_tree_info function in gokart

def test_run_tree_info(self):
        config_file_path = os.path.join(os.path.dirname(__name__), 'test_config.ini')
        luigi.configuration.LuigiConfigParser.add_config_path(config_file_path)
        os.environ.setdefault('test_param', 'test')
        tree_info = gokart.tree_info(mode='simple', output_path='tree.txt')
        with self.assertRaises(SystemExit):
            gokart.run()
        self.assertTrue(gokart.make_tree_info(_DummyTask(param='test')), tree_info.output().load())

def _try_to_send_event_summary_to_slack(slack_api: Optional[gokart.slack.SlackAPI],
                                        event_aggregator: gokart.slack.EventAggregator, cmdline_args: List[str]):
    if slack_api is None:
        # do nothing
        return
    with CmdlineParser.global_instance(cmdline_args) as cp:
        task = cp.get_task_obj()
        tree_info = gokart.make_tree_info(task, details=True)
        task_name = type(task).__name__

    comment = f'Report of {task_name}' + os.linesep + event_aggregator.get_summary()
    content = os.linesep.join([
        '===== Event List ====',
        event_aggregator.get_event_list(),
        os.linesep,
        '==== Tree Info ====',
        tree_info,
    ])
    slack_api.send_snippet(comment=comment, title='event.txt', content=content)