code: def null_context():
      yield
  
imports: from contextlib import contextmanager
  from dataclasses import dataclass
  from enum import auto, Enum
  from functools import lru_cache
  from typing import Dict, List, NamedTuple, Tuple, Union
  import numpy
  import torch
  import torch.nn
  from fairscale.nn import FullyShardedDataParallel
  from vissl.utils.visualize import matplotlib_figure_to_image
label_desc: Use image node_id 4 for calling a global function with example usage: null_context() without return types