/usr/lib/news/control/checkgroups is in inn 1:1.7.2q-44.1ubuntu2.
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 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 | #! /bin/bash
##  $Revision: 1.16 $
##  Checkgroups control-message handler.
PROG=checkgroups
##  Some shells don't pass in $* unless we explicitly pass it in here.
##  =()<. @<_PATH_PARSECTL>@ "$@">()=
. /usr/lib/news/bin/parsecontrol "$@"
case ${ACTION} in
mail)
    export FROM CONTROLPROGS NEWSUSER ARTICLE
    (
	echo "${FROM} posted the following checkgroups message:"
	${SED} -e '/^$/q' -e 's/^/    /' <${ARTICLE}
	echo ''
	echo 'If you want to process it, then feed the body of the'
	echo 'message into docheckgroups while running as the'
	echo "\"${NEWSUSER}\" userid:"
	echo ''
	echo "${CONTROLPROGS}/docheckgroups <<\-EOF-"
	${SED} -e '1,/^$/d' <${ARTICLE}
	echo '-EOF-'
    ) | sed -e 's/^~/~~/' | ${MAILCMD} -s "checkgroups by ${FROM}" ${NEWSMASTER}
    ;;
doit)
    ${SED} -e '1,/^$/d' <${ARTICLE} \
	| ${CONTROLPROGS}/docheckgroups \
	| ${WRITELOG} ${LOGFILE} "checkgroups by ${FROM}"
    ;;
esac
exit
 |