I try to install
ssmtp in Debian 10.0, but get the error
Package ssmtp is not available, but is referred to by another package. This may mean that the package is missing, has been obsoleted, or is only available from another source
But I get no result with neither
apt search ssmpt nor:
$ apt-file search ssmtp monitoring-plugins-basic: /usr/lib/nagios/plugins/check_ssmtp sosreport: /usr/share/sosreport/sos/plugins/ssmtp.py
How do I install ssmtp in Debian buster?