Fitting a list of words to a a regular expression

John D. Cook Consulting seems to do the manner of work that regular programmers like me only dream of doing, and their blog entries are uniformly interesting, educational and somehow esoteric. I’m amazed by them. John D. Cook Consulting’s blog published a post Fitting a regular expression to a list of words where (apparently!) John Cook himself shows how to use a Python library to combine several strings into a regular expression that, when interpreted by a program like grep, will match all those strings.