'Creating a sub DAG within a main DAG\'s context manager'

def test_subdag_in_context_manager(self):

    with DAG('parent', default_args=default_args) as dag:
        subdag = DAG('parent.test', default_args=default_args)
        op = SubDagOperator(task_id='test', subdag=subdag)
        self.assertEqual(op.dag, dag)
        self.assertEqual(op.subdag, subdag)
