code: def __iter__(self):
      return self
  
imports: import copy
  import os
  import traceback
  import six
  import sys
  import numpy
  import paddle
  import paddle.nn.functional
  from copy import deepcopy
  from paddle.io import DataLoader, DistributedBatchSampler
  from .utils import default_collate_fn
  from ppdet.core.workspace import register
  from .None import transform
  from .shm_utils import _get_shared_memory_size_in_M
  from ppdet.utils.logger import setup_logger
label_desc: Use image node_id 4 for calling the BaseSemiDataLoader obj's underlying member method code with example usage: obj.__iter__() and returns: self