As far as I can tell this is the only spot that got overlooked. Rough
test methodology (run inside an hg working copy):
docker run --rm -v pwd:/hg -it debian:wheezy bash
apt-get update
apt-get install python python-dev build-essential unzip mercurial \
wget libbz2-dev
make testpy-2.7.8
You could try and use the system Python, but it's 2.7.3 and has lots
of issues for hg these days that are not worth fixing.