Pyparsing (http://pyparsing.wikispaces.com/Examples) is a Python library that makes it easy to write regex-like expressions that are highly readable, like these lines that will parse "Hello, World!":
from pyparsing import Word, alphas
greet = Word( alphas ) + "," + Word( alphas ) + "!"
greet.parseString("Hello, World!")
It looks like the library is very close to being able to match the power of regexes (see the examples page mentioned above).
