Ensure that this works:

```python
@setup
def mytask():
    print("I am a setup task")

with dag_maker() as dag:
    mytask.override(task_id='newtask')

assert len(dag.task_group.children) == 1
setup_task = dag.task_group.children["newtask"]
assert setup_task._is_setup
```
and teardown also works
assert se_task_group.children.keys() == dag_task_group.children.keys() == expected_children
    @staticmethod
    def assert_task_is_setup_teardown(task, is_setup: bool = False, is_teardown: bool = False):
        assert task._is_setup == is_setup
        assert task._is_teardown == is_teardown
    def test_setup_teardown_tasks(self):
        """
        Test setup and teardown task serialization/deserialization.
        """
        execution_date = datetime(2020, 1, 1)
        with DAG("test_task_group_setup_teardown_tasks", start_date=execution_date) as dag:
            EmptyOperator.as_setup(task_id="setup")
            EmptyOperator.as_teardown(task_id="teardown")
            with TaskGroup("group1"):
                EmptyOperator.as_setup(task_id="setup1")
                EmptyOperator(task_id="task1")
                EmptyOperator.as_teardown(task_id="teardown1")
                with TaskGroup("group2"):
                    EmptyOperator.as_setup(task_id="setup2")
                    EmptyOperator(task_id="task2")
                    EmptyOperator.as_teardown(task_id="teardown2")
        dag_dict = SerializedDAG.to_dict(dag)
        SerializedDAG.validate_schema(dag_dict)
        json_dag = SerializedDAG.from_json(SerializedDAG.to_json(dag))