code: def __iter__(self):
      self.counter = 0
      return self
  
file_path: pytorch-lightning/tests/tests_data/streaming/test_dataloader.py
imports: import torch
  from lightning.data.streaming import CombinedStreamingDataset, StreamingDataLoader
  from torch import tensor
label_desc: Use image node_id 3 for calling the TestStatefulDataset obj's underlying member method code with example usage: obj.__iter__() and returns: self