Getting an error when modifying the faster_rcnn model to add inception_v3 backbone model

[js-kalsi]

I was following this tutorial Modifying the model to add a different backbone. When I replace the mobilenet_v2 model with inception_v3, the code does not work and gives the following error:

  File "/home/gpu-user/projects/building-outline-detection/src/models/faster_rcnn/vision/engine.py", line 46, in train_one_epoch
    loss_dict = model(images, targets)
  File "/home/gpu-user/miniconda3/envs/faster_rcnn/lib/python3.8/site-packages/torch/nn/modules/module.py", line 727, in _call_impl
    result = self.forward(*input, **kwargs)
  File "/home/gpu-user/miniconda3/envs/faster_rcnn/lib/python3.8/site-packages/torchvision/models/detection/generalized_rcnn.py", line 99, in forward
    proposals, proposal_losses = self.rpn(images, features, targets)
  File "/home/gpu-user/miniconda3/envs/faster_rcnn/lib/python3.8/site-packages/torch/nn/modules/module.py", line 727, in _call_impl
    result = self.forward(*input, **kwargs)
  File "/home/gpu-user/miniconda3/envs/faster_rcnn/lib/python3.8/site-packages/torchvision/models/detection/rpn.py", line 330, in forward
    features = list(features.values())
AttributeError: 'InceptionOutputs' object has no attribute 'values'

I am using the following environment:

• Ubuntu 18.04.4 LTS
• CUDA Version: 10.2
• Python: 3.8.6
• Pytorch: 1.7.0

It will be great if someone can help me in resolving this issue.
Thanks