/usr/lib/python2.7/dist-packages/z3c/ptcompat/__init__.py is in python-z3c.ptcompat 1.0.1-0ubuntu1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/python2.7/dist-packages/z3c/ptcompat/../../../../../share/pyshared/z3c/ptcompat/__init__.py