class_docstr: Iterable DataLoader Object
      
class_docstr_tok: ["Iterable","DataLoader","Object"]
code: def _data_generator(self):
      for count, indices in enumerate(self.sampler):
          if count % self.num_workers != self.fid:
              continue
  
          batch_data = [self.dataset[i] for i in indices]
  
          if self.collate_fn is not None:
              yield self.collate_fn(batch_data)
          else:
              yield batch_data
  
imports: import os
  import sys
  import time
  import warnings
  import numpy
  from collections import namedtuple
  import paddle
  from pgl.utils import mp_reader
  from pgl.utils.logger import log
  from pgl.utils.data.dataset import Dataset, StreamDataset
  from pgl.utils.data.sampler import Sampler, StreamSampler
  from pgl.distributed import DistGraphClient, DistGraphServer
  from utils.config import prepare_config
label_desc: Use image node_id 2 for calling the _DataLoaderIter obj's underlying member method code with example usage: obj._data_generator() without return types