amavis software package provides virtual package provided by amavisd-new, you can install in your Debian 9 (Stretch) by running the commands given below on the terminal,
$ sudo apt-get update $ sudo apt-get install amavis
amavis is installed in your system.
Make ensure the amavis package were installed using the commands given below,
$ sudo dpkg-query -l | grep amavis*
You will get with amavis package name, version, architecture and description in a table
| Distro | Debian 9 stretch |
| Section | Virtual packages |
| Package | amavis |
| Version | |
| Description | virtual package provided by amavisd-new |
| Sub Section | Virtual |