Hello! I have a question.
I don`t know the reason about difference you and me.
at first, why you use word instead of original in line 7. you: first = word me: first = original 
secondly, why you delete new_word[0:len(original)].
I just follow instructions, but there is no instructions about deleting new_word[0:len(original)].
I really want to know about it, because I am in stuck.