Remove substring only at the end of string

Question

I have a bunch of strings, some of them have \' rec\'. I want to remove that only if those are the last 4 characters.

So in other words I have

Answer 1

Here is a one-liner version of Jack Kelly's answer along with its sibling:

def rchop(s, sub):
    return s[:-len(sub)] if s.endswith(sub) else s

def lchop(s, sub):
    return s[len(sub):] if s.startswith(sub) else s