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 node.dag is serialized_dag
            try:
                children = node.children.values()
            except AttributeError:
                
                expected_serialized = SerializedBaseOperator.serialize_operator(dag.get_task(node.task_id))
                expected_deserialized = SerializedBaseOperator.deserialize_operator(expected_serialized)
                expected_dict = SerializedBaseOperator.serialize_operator(expected_deserialized)
                assert node
                assert SerializedBaseOperator.serialize_operator(node) == expected_dict
                return
            for child in children:
                check_task_group(child)
        check_task_group(serialized_dag.task_group)
    @staticmethod
    def assert_taskgroup_children(se_task_group, dag_task_group, expected_children):