/usr/lib/python2.7/dist-packages/bitten/htdocs/bitten_build.png is in trac-bitten 0.6+final-3.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/python2.7/dist-packages/bitten/htdocs/../../../../../share/pyshared/bitten/htdocs/bitten_build.png