# cd /usr/ports/net-p2p/deluge
# make PYTHON_VERSION=python3.4 -V_PYTHON_VERSION -VPYTHON_VERSION -Vpython_ARGS
2.7
python3.4
2
#
# make PYTHON_VERSION=python3.4 -VRUN_DEPENDS
...
/usr/local/lib/python3.4/site-packages/twisted/__init__.py:/usr/ports/devel/py-twistedCore
...
That entry is critical. py-twistedCore is only compatible with Python
2 (as stated in the port), but its PYTHON_SITELIBDIR entry gets polluted
with the user-provided PYTHON_VERSION value, although it should refer to
the (optimal) match from python.Mk.