code: def _worker_initializer(dataset):
      """Initializer for processing pool."""
      # global dataset is per-process based and only available in worker processes
      # this is only necessary to handle MXIndexedRecordIO because otherwise dataset
      # can be passed as argument
      global _worker_dataset
      _worker_dataset = dataset
  
imports: import io
  import pickle
  import multiprocessing
  from multiprocessing.reduction import ForkingPickler
  import numpy
  from mxnet import nd
  from mxnet import context
  from mxnet.gluon.data.dataloader import DataLoader, _MultiWorkerIter
  from mxnet.gluon.data.dataloader import default_mp_batchify_fn, default_batchify_fn
label_desc: Use image node_id 4 for calling a global function with example usage: _worker_initializer(dataset) without return types