/usr/lib/python2.7/dist-packages/TraitsBackendWX-3.6.0.egg-info/SOURCES.txt is in python-traitsbackendwx 3.6.0-3.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/python2.7/dist-packages/TraitsBackendWX-3.6.0.egg-info/../../../../share/pyshared/TraitsBackendWX-3.6.0.egg-info/SOURCES.txt