/usr/lib/python3/dist-packages/provisioningserver/templates/pxe/config.poweroff.template is in python3-maas-provisioningserver 2.4.0~beta2-6865-gec43e47e6-0ubuntu1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 | DEFAULT poweroff
LABEL poweroff
{{poweroff}}
|