/usr/lib/python2.6/dist-packages/mastertickets/templates/depgraph.html is in trac-mastertickets 3.0.2+20111224-2.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/python2.6/dist-packages/mastertickets/templates/../../../../../share/pyshared/mastertickets/templates/depgraph.html