Yep - this is a one-way process! You can think of it like an eject from Excel, in the best case.
The devs we've worked with so far have the goal of replacing the Excel process - inheriting it from the team that runs it manually, and automating it fully in Python. From them on, changes to the process would run through a more traditional software-development lifecycle, as you would be editing code.
For these devs - this is a feature not a bug! In Excel, version control, testing, and review is pretty much non-existent...
Cool username btw...