In refpolicy-2.20120215.tar.bz2 is a file 'support/segenxml.py', line 338, has spaces at the beginning of the line but needs a tab to be consistent.
There are quite a few other python files in the reference policy that aren't Python-3 compliant yet :-( Most (all?) of them are fixed in our 2.20120215-r11 (and later) release, currently available on the hardened-dev overlay for testing purposes.
In main tree, ~arch'ed
Stabilized