/usr/lib/python2.7/dist-packages/provisioningserver/tasks.py is in python-maas-provisioningserver 1.2+bzr1373+dfsg-0ubuntu1~12.04.6.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/python2.7/dist-packages/provisioningserver/../../../../share/pyshared/provisioningserver/tasks.py