Append Groups with python - HELP!!

I am working on a addon and i want to be able to append a group from a blend using python. I am having some trouble with working out how to do this.

operator("wm.append", text='2D')

Are you trying to hard-code what to append in some layout code?

Or do you mean to open the file browser for the user?
bpy.ops.wm.append(‘INVOKE_DEFAULT’)

Or append in general by script?

hard-code it to append from the addon folder