Change Default PackerPolicy

I wanted to change DefaultPackerPolicy for my game. I found sample code here; [http://docs.unity3d.com/Documentation/Manual/SpritePacker.html][1] The value I wanted to change is entry.settings.compressionQuality I can’t find any information on what this value is or how to check it. Can anyone provide some help on this? [1]: http://docs.unity3d.com/Documentation/Manual/SpritePacker.html