preinst is in slbackup 0.0.12-5.
This file is a maintainer script. It is executed when installing (*inst) or removing (*rm) the package.
The actual contents of the file can be viewed below.
1 2 3 4 5 | #!/bin/sh
set -e
dpkg-maintscript-helper rm_conffile /etc/cron.daily/slbackup 0.0.12-3 -- "$@"
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