Help with Python script for appending "Groups" to new .blend file

I have this simple python script that is supposed to allow me to append/link a “Group” from one .blend file to my active one. The only problem is, I need it to only append/link the Groups that I specify as apposed to linking all the groups of the .blend file to my new one. No matter how many different groups I create, it seems to link all of them to the new file. Here is my current script… How should I modify it?

start with: blender -P

from Blender import *

for f in files:
groups = Library.LinkableGroups()
if ‘Group’ in groups:
groups= Library.Datablocks(‘Group’)
for g in groups:
Library.Load(g, ‘Group’, 0, 0)
print “added %s” % str(g)