def id_to_path(pk):
    pk = unicode(pk)
    path = [pk[-1]]
    if len(pk) >= 2:
        path.append(pk[-2:])
    else:
        path.append(pk)
    path.append(pk)
    return os.path.join(*path)
Helper function trying to derive the record label taking care of
dataset/ETHPy150Open mozilla/addons-server/src/olympia/amo/helpers.py/id_to_path--crossover with--dataset/ETHPy150Open trungdong/prov/prov/serializers/provxml.py/ProvXMLSerializer._derive_record_label