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
literal = [1, 2, {"a": "b"}]
    real_op = BashOperator.partial(task_id="a", executor_config={"dict": {"sub": "value"}}).expand(
        bash_command=literal
    )
    serialized = SerializedBaseOperator.serialize(real_op)
    assert serialized == {
        "_is_empty": False,
        "_is_mapped": True,
        "_task_module": "airflow.operators.bash",
        "_task_type": "BashOperator",
        "downstream_task_ids": [],
        "expand_input": {
            "type": "dict-of-lists",
            "value": {
                "__type": "dict",
                "__var": {"bash_command": [1, 2, {"__type": "dict", "__var": {"a": "b"}}]},
            },
        },
        "partial_kwargs": {
            "executor_config": {