code: def __iter__(self):
      if self._shuffle:
          self.rng.shuffle(self._lst)
      for dic in self._lst:
          dp = [dic[k] for k in self._keys]
          yield dp
  
file_path: tensorpack/examples/FasterRCNN/common.py
imports: import numpy
  import cv2
  from tensorpack.dataflow import RNGDataFlow
  from tensorpack.dataflow.imgaug import ImageAugmentor, ResizeTransform
label_desc: Use image node_id 3 for calling the DataFromListOfDict obj's underlying member method code with example usage: obj.__iter__() without return types