code: def _ensure_var_is_initialized(var, name):
      """Make sure the input variable is not None."""
      assert var is not None, "{} is not initialized.".format(name)
  
imports: from typing import Optional, List, Union, Tuple
  import torch
  from torch.nn.parallel import DistributedDataParallel
  from apex.multi_tensor_apply import multi_tensor_applier
  from apex.transformer import parallel_state
  from apex.transformer.enums import ModelType
  from apex.transformer.microbatches import build_num_microbatches_calculator
  from apex.transformer.pipeline_parallel._timers import _Timers
label_desc: Use image node_id 2 for calling a global function with example usage: _ensure_var_is_initialized(var, name) without return types