def _feature_process(feature):
    """
    Map function to process batched data inside feature dictionary.
    :param feature: a dictionary contains an image and a label,
                    where image, float32, 0.~1., (h, w, c)
                          label, int32, 0~9, (,)
    :return: a dictionary contains a batch of images and labels
    """
    batched_feature = {
        'images': feature['image'],
        'labels': feature['label']
    }
    return batched_feature