/usr/lib/python2.6/dist-packages/customfieldadmin/__init__.py is in trac-customfieldadmin 0.2.6+r10460-1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/python2.6/dist-packages/customfieldadmin/../../../../share/pyshared/customfieldadmin/__init__.py