<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def reftrack_restricted_data(rt, role, attr):
 """Return the data for restriction of the given attr of the given reftrack :param rt: the :class:`jukeboxcore.reftrack.Reftrack` holds the data :type rt: :class:`jukeboxcore.reftrack.Reftrack` :param role: item data role :type role: QtCore.Qt.ItemDataRole :returns: data for the restriction :rtype: depending on role :raises: None """

    if role == QtCore.Qt.DisplayRole:
        if rt.is_restricted(getattr(rt, attr, None)):
            return "Restricted"
        else:
            return "Allowed"