Ian Bicking: the old part of his blog

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I just used iterating over a string yesterday to walk through a string representing a potential Hardware Address (aka MAC address) one digit at a time. I was checking for valid digits. I had a regex solution working, but I always look for ways to avoid them when possible.

So yeah, I think they're useful, but I don't know if I really "need" them or not. In this case, I thought it was the easiest to understand.
Comment on Python nit, chapter 3
by John P Speno