code: def _to_device(device: DeviceType) -> torch.device:
      device = torch.device(device)
      if device.type != "cuda":
          raise ValueError(
              "`set_devices` expect a list of CUDA devices, but got "
              f"device type {device.type}."
          )
      return device
  
file_path: pytorch/torch/distributed/rpc/options.py
imports: from typing import Dict, List, Optional, Union
  import torch
  from torch._C._distributed_rpc import _TensorPipeRpcBackendOptionsBase
  from .None import constants
label_desc: Use image node_id 1 for calling a global function with example usage: _to_device(device) and returns: device