/usr/share/debhelper/autoscripts/postrm-xmlcatalog is in xml-core 0.13+nmu2.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 | if [ "$1" = "purge" ]; then
rm -f #PACKAGECAT# #PACKAGECAT#.old
fi
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