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
whenever no matches are found.
        :param context: Execution Context Dictionary
        :param key: A key for the XCom. If provided, only XComs with matching
            keys will be returned. The default key is 'return_value', also
            available as a constant XCOM_RETURN_KEY. This key is automatically
            given to XComs returned by tasks (as opposed to being pushed
            manually). To remove the filter, pass key=None.
        :param task_ids: Only XComs from tasks with matching ids will be
            pulled. Can pass None to remove the filter.
        :param dag_id: If provided, only pulls XComs from this DAG.
            If None (default), the DAG of the calling task is used.
        :param include_prior_dates: If False, only XComs from the current
            execution_date are returned. If True, XComs from previous dates
            are returned as well.
        """
        return context["ti"].xcom_pull(
            key=key, task_ids=task_ids, dag_id=dag_id, include_prior_dates=include_prior_dates
        )
    @classmethod
    def get_serialized_fields(cls):
        """Stringified DAGs and operators contain exactly these fields."""
        if not cls.__serialized_fields:
            from airflow.models.dag import DagContext
            
            
            
            
            DagContext.push_context_managed_dag(None)
            cls.__serialized_fields = frozenset(
                vars(BaseOperator(task_id="test")).keys()