code: def get_data_parallel_group() -> torch.distributed.ProcessGroup:
      """Get the data parallel group the caller rank belongs to."""
      assert (
          _DATA_PARALLEL_GROUP is not None
      ), "data parallel group is not initialized"
      return _DATA_PARALLEL_GROUP
  
file_path: fairscale/fairscale/nn/model_parallel/initialize.py
imports: from typing import List, Optional
  import torch
  from .utils import ensure_divisibility
label_desc: Use image node_id 4 for calling a global function with example usage: get_data_parallel_group() and returns: _DATA_PARALLEL_GROUP