class_docstr: Load MOT dataset with MOT format from image stream.
  Args:
      keep_ori_im (bool): whether to keep original image, default False.
          Set True when used during MOT model inference while saving
          images or video, or used in DeepSORT.
code: def __iter__(self):
      ct = 0
      while True:
          if self.imagequeue:
              frame = self.imagequeue.popleft()
              imgname = os.path.join(
                  self.frameraw_dir, "frame{}.png".format(ct)
              )
              cv2.imwrite(imgname, frame)
              image = imread(imgname)
              rec = {"im_id": np.array([ct]), "im_file": imgname}
              if self.keep_ori_im:
                  rec.update({"keep_ori_im": 1})
              rec["curr_iter"] = self._curr_iter
              self._curr_iter += 1
              ct += 1
              if self.transform:
                  yield self.transform(rec)
              else:
                  yield rec
          else:
              return
  
imports: import numbers
  import os
  import sys
  from collections import deque
  from collections.abc import Mapping
  import six
  from ppdet.core.workspace import register, serializable
  from ppdet.utils.logger import setup_logger
  from ppdet.data.reader import BaseDataLoader, Compose
  import cv2
  from imageio import imread, imwrite
  import numpy
  import paddle
  from paddle.framework import core
label_desc: Use image node_id 7 for calling the MOTImageStream obj's underlying member method code with example usage: obj.__iter__() without return types