code: def test_image_set_transform(self):
      transformer = ImageMatToTensor()
      image_set = ImageSet.read(self.image_path)
      transformed = image_set.transform(transformer)
      transformed.get_image()
  
imports: import pytest
  import cv2
  from bigdl.dllib.nncontext import *
  from bigdl.dllib.feature.image import *
label_desc: Use image node_id 8 for calling the Test_Image_Set obj's underlying member method code with example usage: obj.test_image_set_transform() without return types