/usr/lib/python2.7/dist-packages/zope.app.basicskin-3.5.1-nspkg.pth is in python-zope.app.basicskin 3.5.1-0ubuntu3.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/python2.7/dist-packages/../../../share/pyshared/zope.app.basicskin-3.5.1-nspkg.pth