code: def _read(self, file_path: str):
      return itertools.islice(
          cycle_iterator_function(
              lambda: [Instance({"label": LabelField("A")})]
          ),
          100,
      )
  
file_path: allennlp/tests/data/data_loaders/multitask_data_loader_test.py
imports: import itertools
  import pytest
  import torch
  from allennlp.common.util import cycle_iterator_function
  from allennlp.data import DatasetReader, Instance, Vocabulary
  from allennlp.data.fields import LabelField
  from allennlp.data.dataset_readers import MultiTaskDatasetReader
  from allennlp.data.data_loaders.multitask_data_loader import MultiTaskDataLoader
  from allennlp.data.data_loaders.multitask_scheduler import RoundRobinScheduler
  from allennlp.data.data_loaders.multitask_epoch_sampler import UniformSampler, WeightedSampler
label_desc: Use image node_id 1 for calling the FakeDatasetReaderA obj's underlying member method code with example usage: obj._read(file_path) and returns: itertools