/usr/lib/python2.7/dist-packages/CedarBackup2/filesystem.py is in cedar-backup2 2.27.0-2.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/python2.7/dist-packages/CedarBackup2/../../../../share/pyshared/CedarBackup2/filesystem.py