code: def backward(ctx, grad_output):
      raise NotImplementedError(
          "backward not implemented", JPEGEncodingDecoding
      )
  
file_path: advertorch/advertorch/functional.py
imports: import torch
  from torchvision import transforms
  from PIL import Image
label_desc: Use image node_id 2 for calling the JPEGEncodingDecoding obj's underlying member method code with example usage: obj.backward(ctx, grad_output) without return types