Creating an interactive web application in Python which will be based on a model created in FORTRAN

I am new to Python and currently in the process of learning it. I want to achieve a task in which I have to create a web application based on a model created earlier. The model is created using FORTRAN.

For the web application, I am choosing PYTHON as the language of preference with the DJANGO framework.

1) I wanted to know, do I need to mimic the behavior which the model has in python or is it a better idea to call that model in the web application and have the user interact with the model directly. Personally I think the application might be clunky if we are calling the model directly inside the application.

Please let me know if you need any further clarifications.

Thanks