Fix Python – Stripping everything but alphanumeric chars from a string in Python

What is the best way to strip all non alphanumeric characters from a string, using Python?
The solutions presented in the PHP variant of this question will probably work with some minor adjustments, but don’t seem very ‘pythonic’ to me.
For the record, I don’t just want to strip periods and commas (and other punctuation), but also quotes, bracket….