/usr/lib/python2.7/dist-packages/softwareproperties/AptAuth.py is in python-software-properties 0.82.7.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/python2.7/dist-packages/softwareproperties/../../../../share/pyshared/softwareproperties/AptAuth.py