Lab9: Can't run python api_server/app.py

[astrogopher]

I've been following along with the course, and on lab 9 section "Serving predictions from a web server" when I go to call

python api_server/app.py

I get the following error:

`(fsdl-text-recognizer-2021) astrogopher@astrogopher lab9 % python api_server/app.py
Traceback (most recent call last):
File "api_server/app.py", line 14, in
model = ParagraphTextRecognizer()

File "/Users/astrogopher/fsdl-text-recognizer-2021-labs/lab9/text_recognizer/paragraph_text_recognizer.py", line 35, in init
checkpoint_path=CONFIG_AND_WEIGHTS_DIRNAME / "model.pt", args=args, model=model

File "/Users/astrogopher/opt/miniconda3/envs/fsdl-text-recognizer-2021/lib/python3.6/site-packages/pytorch_lightning/core/saving.py", line 135, in load_from_checkpoint
checkpoint = pl_load(checkpoint_path, map_location=lambda storage, loc: storage)

File "/Users/astrogopher/opt/miniconda3/envs/fsdl-text-recognizer-2021/lib/python3.6/site-packages/pytorch_lightning/utilities/cloud_io.py", line 32, in load
return torch.load(f, map_location=map_location)

File "/Users/astrogopher/opt/miniconda3/envs/fsdl-text-recognizer-2021/lib/python3.6/site-packages/torch/serialization.py", line 595, in load
return _legacy_load(opened_file, map_location, pickle_module, **pickle_load_args)

File "/Users/astrogopher/opt/miniconda3/envs/fsdl-text-recognizer-2021/lib/python3.6/site-packages/torch/serialization.py", line 764, in _legacy_load
magic_number = pickle_module.load(f, **pickle_load_args)
_pickle.UnpicklingError: invalid load key, 'v'.
`