I didn’t see your post on the fastai forum, but that’s probably a better place to have this discussion. You are mixing two versions of the library in that setup.py file.
The fact you’re using export_file_name = 'New_P100.pkl' and load_learner suggests you’re on the latest API, but at the same time you use load_learner with a wrong syntax (it takes path, export_file_name and that’s pretty much it since your whole Learner has been serialized) and learn.load (which is the line that calls torch.load behind the scenes with a variable that I don’t see defined in the code (model_file_name).