How to replace the some characters from the end of a string?

Question

I want to replace characters at the end of a python string. I have this string:

 s = \"123123\"

I want to replace the last 2 with

Answer 1

For the second example, I would recommend rsplit, as it is very simple to use and and directly achieves the goal. Here is a little function with it:

def replace_ending(sentence, old, new):
    if sentence.endswith(old):
        i = sentence.rsplit(old,1)
        new_sentence =new.join(i)
        return new_sentence
    return sentence

print(replace_ending("aaa bbb aaa bbb", "bbb", "xxx")) 

Output:

aaa bbb aaa xxx