How to convert matlab code to python code automatically
Unfortunately, no such tool exists, especially for complex things like conversion of toolboxes.
I suggest that you try to find places in your codebase where you could divide your logic into self-contained modules. Then, you can work on converting your code one module at a time. You should already start to familiarize with numpy which will serve as the replacement for the majority of your matrix math operations. Then you will need to find ways to patch together your code using tools like the MATLAB engine.
Its worth noting that converting Python 2 to 3 is relatively straightforward and there is an official tool (2to3) that can help you do this automatically. However, be careful with converter like the one you found, a quick scan of their github shows 65 outstanding issues and no updates for nearly 3 years.
Good luck with the conversion, although it will not be as easy as you may have hoped, it will be worth in in the long run.
I think the short answer is that there is no such tool that will do this reliably.
You can use matlab code though in python and opposite using the matlab engine API, but there are some limitations. Have a look for more details in the doc here