code: def test_topological_group_dep():
      execution_date = pendulum.parse("20200101")
      with DAG("test_dag_edges", start_date=execution_date) as dag:
          task1 = EmptyOperator(task_id="task1")
          task6 = EmptyOperator(task_id="task6")
          with TaskGroup("group_a") as group_a:
              task2 = EmptyOperator(task_id="task2")
              task3 = EmptyOperator(task_id="task3")
          with TaskGroup("group_b") as group_b:
              task4 = EmptyOperator(task_id="task4")
              task5 = EmptyOperator(task_id="task5")
  
          task1 >> group_a >> group_b >> task6
  
      def nested_topo(group):
          return [
              nested_topo(node) if isinstance(node, TaskGroup) else node
              for node in group.topological_sort()
          ]
  
      topological_list = nested_topo(dag.task_group)
  
      assert topological_list == [
          task1,
          [
              task2,
              task3,
          ],
          [
              task4,
              task5,
          ],
          task6,
      ]
  
imports: from __future__ import annotations
  from datetime import timedelta
  import pendulum
  import pytest
  from airflow.decorators import dag, setup, task, task_group, teardown
  from airflow.exceptions import TaskAlreadyInTaskGroup
  from airflow.models.baseoperator import BaseOperator
  from airflow.models.dag import DAG
  from airflow.models.xcom_arg import XComArg
  from airflow.operators.bash import BashOperator
  from airflow.operators.empty import EmptyOperator
  from airflow.operators.python import PythonOperator
  from airflow.utils.dag_edges import dag_edges
  from airflow.utils.task_group import TaskGroup, task_group_to_dict
  from tests.models import DEFAULT_DATE
label_desc: Use image node_id 27 for calling a global function with example usage: test_topological_group_dep() and returns: unknown