I can't install dev-python/pytz and dev-python/pygments with =dev-lang/python-3.1.4-r2 installed. With =dev-lang/python-3.1.3-r1 OK.
Created attachment 282951 [details]
build.log for dev-python/pytz-2011e
Please post your `emerge --info' output as well.
Created attachment 283591 [details]
emerge --info =dev-python/pytz-2011e
You were mixing new versions of dev-lang/python with old versions of dev-python/setuptools. Older versions of dev-python/setuptools now block newer versions of dev-lang/python, so this bug can be closed.