code: def ray_2_node_4_gpu():
      cluster = Cluster()
      for _ in range(2):
          cluster.add_node(num_cpus=2, num_gpus=4)
  
      ray.init(address=cluster.address)
  
      yield
  
      ray.shutdown()
      cluster.shutdown()
  
file_path: ray/python/ray/train/tests/conftest.py
imports: import logging
  import boto3
  import pytest
  import ray
  from ray._private.test_utils import simulate_storage
  from ray.cluster_utils import Cluster
  from ray.tests.conftest import propagate_logs
  from ray.tests.conftest import pytest_runtest_makereport
label_desc: Use image node_id 9 for calling a global function with example usage: ray_2_node_4_gpu() without return types