[throwawaaarrgh]

oh come on, whatever is feeding files to the function I'll just trick into using some other data with different files. you don't need to "execute data" to have substitution bugs.

and it's easy to add status checks to your shell script just like you can for Python. exceptions are not the only way to stop on error. but it's sure a hell of a lot easier to have a non-working program in Python, whereas it's a lot easier for a shell script to keep working.