'Subdags and subdag tasks can\'t both have a pool with 1 slot'

def test_subdag_pools(self):

    dag = DAG('parent', default_args=default_args)
    subdag = DAG('parent.child', default_args=default_args)
    session = airflow.settings.Session()
    pool_1 = airflow.models.Pool(pool='test_pool_1', slots=1)
    pool_10 = airflow.models.Pool(pool='test_pool_10', slots=10)
    session.add(pool_1)
    session.add(pool_10)
    session.commit()
    dummy_1 = DummyOperator(task_id='dummy', dag=subdag, pool='test_pool_1')
    self.assertRaises(AirflowException, SubDagOperator, task_id='child', dag=dag, subdag=subdag, pool='test_pool_1')
    dag = DAG('parent', default_args=default_args)
    SubDagOperator(task_id='child', dag=dag, subdag=subdag, pool='test_pool_10')
    session.delete(pool_1)
    session.delete(pool_10)
    session.commit()
