I have several python products I have built packages for, but need
certain environment variables set while building, installing and
using. Since they require env variables just to build, and you
normally don't know this until after you build a package, it would
seem nice to set the env variable in the pkg makefile. Since these
use setup.py, a normal make variable isn't adequate (these setup.py
scripts explicitly look in the environment). Currently I just use
something like the following:

SYBASE=${LOCALBASE}/freetds