class_docstr: Implements manual multi-process and distributed sharding (MMPDS).
class_docstr_tok: ["Implements","manual","multi-process","and","distributed","sharding","(","MMPDS",")","."]
code: def _read(self, file_path):
      for i in self.shard_iterable(range(TOTAL_INSTANCES)):
          yield self.text_to_instance(i)
  
imports: from itertools import islice
  from typing import Optional, List, Set
  import pytest
  import torch.distributed
  from allennlp.common import util
  from allennlp.data import Instance
  from allennlp.data.dataset_readers import DatasetReader, WorkerInfo
  from allennlp.data.fields import LabelField
label_desc: Use image node_id 2 for calling the MockMmpdsDatasetReader obj's underlying member method code with example usage: obj._read(file_path) without return types