def convert_to_int(val):
        ....

The problem with Python - and non-statically-typed languages in general - is that function signatures don't need to be defined upfront, which leaves it up to the programmer to figure out the inner workings of the functions. This is a huge pain point when working with other people's code.

Python 3 introduced function annotations, which is great. But again, the problem here is that function annotations are opt-in. It's still up to the developer to add the annotations.

I know I'm going to get some crap for this, but for big prod systems I prefer C++.