code: def test_imageiter(self):
      im_list = [[np.random.randint(0, 5), x] for x in self.IMAGES]
      fname = "./data/test_numpy_imageiter.lst"
      file_list = [
          "\t".join([str(k), str(np.random.randint(0, 5)), x])
          for k, x in enumerate(self.IMAGES)
      ]
      with open(fname, "w") as f:
          for line in file_list:
              f.write(line + "\n")
  
      test_list = ["imglist", "path_imglist"]
      for dtype in ["int32", "float32", "int64", "float64"]:
          for test in test_list:
              imglist = im_list if test == "imglist" else None
              path_imglist = fname if test == "path_imglist" else None
              imageiter_list = [
                  mx.gluon.contrib.data.vision.ImageDataLoader(
                      2,
                      (3, 224, 224),
                      imglist=imglist,
                      path_imglist=path_imglist,
                      path_root="",
                      dtype=dtype,
                  ),
                  mx.gluon.contrib.data.vision.ImageDataLoader(
                      3,
                      (3, 224, 224),
                      imglist=imglist,
                      path_imglist=path_imglist,
                      path_root="",
                      dtype=dtype,
                      last_batch="discard",
                  ),
                  mx.gluon.contrib.data.vision.ImageDataLoader(
                      3,
                      (3, 224, 224),
                      imglist=imglist,
                      path_imglist=path_imglist,
                      path_root="",
                      dtype=dtype,
                      last_batch="keep",
                  ),
                  mx.gluon.contrib.data.vision.ImageDataLoader(
                      3,
                      (3, 224, 224),
                      imglist=imglist,
                      path_imglist=path_imglist,
                      path_root="",
                      dtype=dtype,
                      last_batch="rollover",
                  ),
                  mx.gluon.contrib.data.vision.ImageDataLoader(
                      3,
                      (3, 224, 224),
                      imglist=imglist,
                      shuffle=True,
                      path_imglist=path_imglist,
                      path_root="",
                      dtype=dtype,
                      last_batch="keep",
                      rand_crop=1,
                      rand_gray=0.1,
                      rand_mirror=True,
                  ),
              ]
              for it in imageiter_list:
                  for _ in it:
                      pass
  
file_path: mxnet/tests/python/unittest/test_numpy_contrib_gluon_data_vision.py
imports: import mxnet
  import numpy
  from mxnet.test_utils import *
  import sys
  import shutil
  import tempfile
  import unittest
  import pytest
label_desc: Use image node_id 3 for calling the TestImage obj's underlying member method code with example usage: obj.test_imageiter() without return types