How do I compare version numbers in Python?

I am walking a directory that contains eggs to add those eggs to the sys.path. If there are two versions of the same .egg in the directory, I want to add only the latest one.

I have a regular expression r"^(?P<eggName>\w+)-(?P<eggVersion>[\d\.]+)-.+\.egg$ to extract the name and version from the filename. The problem is comparing the version number, which is a string like 2.3.1.

Since I’m comparing strings, 2 sorts above 10, but that’s not correct for versions.

>>> "2.3.1" > "10.1.1"
True

I could do some splitting, parsing, casting to int, etc., and I would eventually get a workaround. But this is Python, not Java. Is there an elegant way to compare version strings?

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