---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
<ipython-input-132-458f2a368d22> in <module>()
      1 # create training dataset
----> 2 create_tfrecord_dataset(train_images_filename_list, train_writer)

<ipython-input-131-a05899e637db> in create_tfrecord_dataset(filename_list, writer)
     15                 continue
     16         try:
---> 17             annotation_np = read_annotation_from_mat_file(annotations_dir_aug_voc, image_name)
     18         except FileNotFoundError:
     19             # read from Pascal VOC path

<ipython-input-130-f033846eb6a6> in read_annotation_from_mat_file(annotations_dir, image_name)
      1 def read_annotation_from_mat_file(annotations_dir, image_name):
      2     annotations_path = os.path.join(annotations_dir, (image_name.strip() + ".mat"))
----> 3     mat = spio.loadmat(annotations_path)
      4     img = mat['GTcls']['Segmentation'][0][0]
      5     return img

~\Anaconda3\envs\tensorflow\lib\site-packages\scipy\io\matlab\mio.py in loadmat(file_name, mdict, appendmat, **kwargs)
    139     """
    140     variable_names = kwargs.pop('variable_names', None)
--> 141     MR, file_opened = mat_reader_factory(file_name, appendmat, **kwargs)
    142     matfile_dict = MR.get_variables(variable_names)
    143     if mdict is not None:

~\Anaconda3\envs\tensorflow\lib\site-packages\scipy\io\matlab\mio.py in mat_reader_factory(file_name, appendmat, **kwargs)
     62 
     63     """
---> 64     byte_stream, file_opened = _open_file(file_name, appendmat)
     65     mjv, mnv = get_matfile_version(byte_stream)
     66     if mjv == 0:

TypeError: 'NoneType' object is not iterable