Add Instructions for Model Retraining

[anniestaker]

No description provided.

[coveralls]

coverage: 94.737% (+0.04%) from 94.694%
when pulling 3063356 on annie/retrain-example
into 01f425e on main.

[sarah-innis]

instead of referring to the jupyter notebook for the training my thought would be to refer them to these functions instead? walandmarks/helpers
/landmark_classification_model_training.py I think you would just run lines 304 to 342?

[Ivaldivi]

Yes, in theory, if someone wants to retrain the model they would just call create_train_analyze_model from that .py file. I can add a main guard (if name == 'main') that contains the function call so it's ready for the model-maintainer but doesn't get called during unittesting

[anniestaker]

Okay. I added a main guard and did some tweaking of the function. I also updated the doc strings and tests.

Then I updated the instruction file to use this function instead of the notebook.