$ sudo apt-get update
$ sudo apt-get install libgravatar-url-perl 

libgravatar-url-perl is installed in your system.

Make ensure the libgravatar-url-perl package were installed using the commands given below,

$ sudo dpkg-query -l | grep libgravatar-url-perl *

You will get with libgravatar-url-perl package name, version, architecture and description in a table

libgravatar-url-perl package basic information: