/usr/share/debhelper/autoscripts/postinst-upstart is in debhelper 9.20120115ubuntu3.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 | if [ -e "/etc/init/#JOB#.conf" ]; then
invoke-rc.d #JOB# start || #ERROR_HANDLER#
fi
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