/usr/lib/python2.7/dist-packages/w3lib/util.py is in python-w3lib 1.5-1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/python2.7/dist-packages/w3lib/../../../../share/pyshared/w3lib/util.py
/usr/lib/python2.7/dist-packages/w3lib/../../../../share/pyshared/w3lib/util.py