Replacing substrings given a dictionary of strings-to-be-replaced as keys and replacements as values. Python

Question

I have a dictionary with the strings to be replaced as keys and its replacement as values. Other than looking through the stri

Answer 1

re.sub can call a function that returns the substitution

segmenter = {'foobar':'foo bar', 'withoutspace':'without space', 'barbar': 'bar bar'}
sentence = "this is a foobar in a barbar withoutspace"

import re

def fn(match):
    return segmenter[match.group()]

print re.sub('|'.join(re.escape(k) for k in segmenter), fn, sentence)