/var/lib/cobbler/kickstarts/default.ks is in maas-provision-common 2.2.2-0ubuntu4.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 | # this file intentionally left blank
# admins: edit it as you like, or leave it blank for non-interactive install
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