/usr/lib/python2.7/dist-packages/envisage-4.4.0.egg-info/requires.txt is in python-envisage 4.4.0-1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/python2.7/dist-packages/envisage-4.4.0.egg-info/../../../../share/pyshared/envisage-4.4.0.egg-info/requires.txt