code: def ray_start_4_cpus():
      address_info = ray.init(num_cpus=4)
      yield address_info
      # The code after the yield will run as teardown code.
      ray.shutdown()
  
file_path: ray/python/ray/train/tests/test_horovod_trainer.py
imports: import os
  import pytest
  import torch
  import torch.nn
  from torch.utils.data import DataLoader
  from torchvision import datasets
  from torchvision.transforms import transforms
  import ray
  from ray.train import ScalingConfig
  from ray.train.examples.horovod.horovod_pytorch_example import Net
  from ray.train.examples.horovod.horovod_pytorch_example import train_func
  from ray.train.horovod import HorovodTrainer
  from ray.train.torch import TorchPredictor
label_desc: Use image node_id 1 for calling a global function with example usage: ray_start_4_cpus() without return types