No more mixed types for inputs.

Because (int or float) will always be true.

You probably wanted isinstance(r, (int, float)), although typechecking is rarely the correct solution in Python.

It works, but by now I assumed you have noticed Python accepts negative indices both for arrays and strings (well, tuples too, but let's keep it simple).

I encourage you to resubmit with smarter or just different solutions once you get to read them. Keep up the good work and happy coding :)!

Java version desperately needs clarification in descripton. It asks to return a number or false. I didn't realise before after implementing object returning that its actually asking for IllegalArgumentException.