code: def __init__(self, ds, index=0):
      def func(im_data):
          img = cv2.imdecode(im_data, cv2.IMREAD_COLOR)
          return img
  
      super(ImageDecode, self).__init__(ds, func, index=index)
  
imports: import argparse
  import numpy
  import os
  import zipfile
  import cv2
  from tensorpack import LMDBSerializer, MapDataComponent, RNGDataFlow
label_desc: Use image node_id 1 to create a new ImageDecode object from inherited base classes: MapDataComponent with example: obj = ImageDecode(ds, index)