Yes,
You are using python, but it looks like you need to borrow shinystan from r for diagnostics.
unfortunately there doesn’t seem to be an easy way to use shinystan from python at this stage:
Good workflow for getting samples from PyStan (python) into ShinyStan ®? - General - The Stan Forums (mc-stan.org)
So that might be the general issue you are facing. It might be smart to try importing your data into r as you can then make use of brms and shinystan, which could speed your development time considerably. Easy to pick up, and totally worth your efforts I suggest.