class_docstr: A very simple `DataLoader` that is mostly used for testing.
code: def set_target_device(self, device: torch.device) -> None:
      self.cuda_device = device
  
imports: import math
  import random
  from typing import Optional, List, Iterator
  import torch
  from allennlp.common.util import lazy_groups_of
  from allennlp.common.tqdm import Tqdm
  from allennlp.data.data_loaders.data_loader import DataLoader, TensorDict
  from allennlp.data.data_loaders.data_collator import DefaultDataCollator
  from allennlp.data.dataset_readers import DatasetReader
  from allennlp.data.instance import Instance
  from allennlp.data.vocabulary import Vocabulary
  import allennlp.nn.util
label_desc: Use image node_id 7 for calling the SimpleDataLoader obj's underlying member method code with example usage: obj.set_target_device(device) without return types