def entry_key(*entry):
    """:return: Key suitable to be used for the index.entries dictionary
    :param entry: One instance of type BaseIndexEntry or the path and the stage"""
    if len(entry) == 1:
        return (entry[0].path, entry[0].stage)
    else:
        return tuple(entry)
:return: Key suitable to be used for the index.entries dictionary
    :param entry: One instance of type BaseIndexEntry or the path and the stage