/usr/lib/cruft/explain/init-system-helpers is in cruft-common 0.9.34.
This file is owned by root:root, with mode 0o755.
The actual contents of the file can be viewed below.
1 2 3 4 5 | #!/bin/dash
set -e
file /etc/rc?.d/[SK]???* |
egrep ": *symbolic link to \`?../init.d/[-a-zA-Z0-9_.]*'?$" |
sed "s/: *symbolic.*$//"
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