class_docstr: Image iterator with a large number of augmentation choices for detection.
  
  Parameters
  ----------
  batch_size : int
      Number of examples per batch.
  data_shape : tuple
      Data shape in (channels, height, width) format.
      For now, only RGB image with 3 channels is supported.
  path_imgrec : str
      Path to image record file (.rec).
      Created with tools/im2rec.py or bin/im2rec.
  path_imglist : str
      Path to image list (.lst).
      Created with tools/im2rec.py or with custom script.
      Format: Tab separated record of index, one or more labels and relative_path_from_root.
  imglist: list
      A list of images with the label(s).
      Each item is a list [imagelabel: float or list of float, imgpath].
  path_root : str
      Root folder of image files.
  shuffle : bool
      Whether to shuffle all images at the start of each iteration or not.
      Can be slow for HDD.
  aug_list : list or None
      Augmenter list for generating distorted images
  part_index : int
      Partition index.
  num_parts : int
      Total number of partitions.
  last_batch : {'keep', 'discard', 'rollover'}
      How to handle the last batch if batch_size does not evenly divide
      `len(dataset)`.
  
      keep - A batch with less samples than previous batches is returned.
      discard - The last batch is discarded if its incomplete.
      rollover - The remaining samples are rolled over to the next epoch.
  kwargs : ...
      More arguments for creating augmenter. See mx.gluon.contrib.data.create_bbox_augment.
code: def __len__(self):
      return len(self._iter)
  
imports: import logging
  import numpy
  from .....None import ndarray
  from .....util import is_np_array
  from .....None import numpy
  from ....nn import HybridSequential, Sequential, HybridBlock, Block
  from ....data.vision import transforms
  from ....data import DataLoader
  from .transforms import bbox
label_desc: Use image node_id 3 for calling the ImageBboxDataLoader obj's underlying member method code with example usage: obj.__len__() and returns: len