Pytz 2013b Fails with PIP 1.4

UPDATE: Pytz is now using a numeric naming convention (i.e. 2013.7) which fixes this bug.

The latest version of PIP only installs stable versions by default, meaning anything with a pre-release version name will be ignored. Unfortunately the Pytz naming convention looks like a beta release (2013b) when it is actually the second release of 2013.

More on this bug can be found here:
https://bugs.launchpad.net/pytz/+bug/1204837

For now the workaround is to add the version when installing:

pip install pytz==2013b