Replacing unquoted words only in Python

Question

I am looking for a way to replace a word, however only when its not surounded by quotations.

For example Replacing Hello with Hi

Answer 1

Regular expressions are awesome:

>>>import re

>>>expression = re.compile("(?!(\"|'))Hello(?!(\"|'))")
>>>expression.sub("Hi",'This string says "Hello" and Hello')

This string says "Hello" and Hi

The only problem with that is that it will also fail to replace "Hello and Hello", if that becomes an issue you can add specific cases for them.