code: def test_trigger_tasks(self):
      execute_mock = MagicMock()
      executor = DebugExecutor()
      executor.execute_async = execute_mock
  
      executor.queued_tasks = {
          "t1": (None, 1, None, MagicMock(key="t1")),
          "t2": (None, 2, None, MagicMock(key="t2")),
      }
  
      executor.trigger_tasks(open_slots=4)
      assert not executor.queued_tasks
      assert len(executor.running) == 2
      assert len(executor.tasks_to_run) == 2
      assert not execute_mock.called
  
file_path: airflow/tests/executors/test_debug_executor.py
imports: from __future__ import annotations
  from unittest import mock
  from unittest.mock import MagicMock
  from airflow.executors.debug_executor import DebugExecutor
  from airflow.utils.state import State
label_desc: Use image node_id 4 for calling the TestDebugExecutor obj's underlying member method code with example usage: obj.test_trigger_tasks() without return types