/usr/lib/python2.7/dist-packages/twisted/plugins/tftp_plugin.py is in python-txtftp 0.1~bzr38-0ubuntu2.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/python2.7/dist-packages/twisted/plugins/../../../../../share/pyshared/twisted/plugins/tftp_plugin.py