code: def maybe_init_stream(self) -> None:
      if self.is_gpu:
          self.stream = self.module.Stream()
          self.stream_context = partial(
              self.module.stream,
              stream=self.stream,
          )
  
file_path: pytorch_geometric/torch_geometric/loader/prefetch.py
imports: import warnings
  from contextlib import nullcontext
  from functools import partial
  from typing import Any, Optional
  import torch
  from torch.utils.data import DataLoader
  from torch_geometric.typing import WITH_IPEX
label_desc: Use image node_id 2 for calling the DeviceHelper obj's underlying member method code with example usage: obj.maybe_init_stream() without return types