erubis software package provides virtual package provided by ruby-erubis, 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 erubis
erubis is installed in your system.
Make ensure the erubis package were installed using the commands given below,
$ sudo dpkg-query -l | grep erubis*
You will get with erubis package name, version, architecture and description in a table
| Distro | Debian 9 stretch |
| Section | Virtual packages |
| Package | erubis |
| Version | |
| Description | virtual package provided by ruby-erubis |
| Sub Section | Virtual |