def persistent_twin_id(obj):
    """Twin Pickler for inter-twinterpeter communication"""
    try:
        __import_mod_name__ = obj.__import_mod_name__
        if isinstance(obj, type):
            raise AttributeError
    except AttributeError:
        return None
    else:
        return '%s\t%s\t%s\t%s' % (obj.__instance_id__, obj.__twin_id__,
            __import_mod_name__[0], __import_mod_name__[1])
