I have written several Python tools for my company.  Is there any good reason to convert them from Python to C# now that their usefulness has been proven?  Would I be better off just leaving them in Python?
If you're the only Python developer in a C# shop, then it makes plenty of sense to convert.  If you quit tomorrow, no one will be able to maintain these systems.
Is there any good reason to convert an app written in python to c#?