code: def test_actor_method_fail(ray_start_2_cpus):
      ag = ActorGroup(actor_cls=DummyActor, num_actors=2)
  
      with pytest.raises(TypeError):
          ag.return_arg(1)
  
      with pytest.raises(AttributeError):
          ag.non_existent_method.remote()
  
file_path: ray/python/ray/tests/test_actor_group.py
imports: import time
  import warnings
  import pytest
  import ray
  from ray.util.actor_group import ActorGroup
label_desc: Use image node_id 7 for calling a global function with example usage: test_actor_method_fail(ray_start_2_cpus) without return types