def uniq(alist): # Fastest order preserving
    ''' Helper from comments in http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/52560 '''
    set = {}
    return [set.setdefault(e,e) for e in alist if e not in set]
 Helper from comments in http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/52560 
recipes/Python/576397_Listing_packagepatches_dependencies_binary/recipe-576397.py