postinst is in odt2txt 0.5-1build1.
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 6 7 8 9 10 | #!/bin/sh
set -e
if [ "$1" = configure ]; then
	update-alternatives --quiet --install /usr/bin/odt2txt odt2txt \
		/usr/bin/odt2txt.odt2txt 200 --slave /usr/share/man/man1/odt2txt.1.gz \
		odt2txt.1.gz /usr/share/man/man1/odt2txt.odt2txt.1.gz
fi
 |