$ sudo apt-get update
$ sudo apt-get install macopix-gtk2 

macopix-gtk2 is installed in your system.

Make ensure the macopix-gtk2 package were installed using the commands given below,

$ sudo dpkg-query -l | grep macopix-gtk2 *

You will get with macopix-gtk2 package name, version, architecture and description in a table

macopix-gtk2 package basic information: