str: A unique identifier for all players in a household.

        Looks like: ``'Sonos_asahHKgjgJGjgjGjggjJgjJG34'``

def household_id(self):
        """str: A unique identifier for all players in a household.

        Looks like: ``'Sonos_asahHKgjgJGjgjGjggjJgjJG34'``
        """
        # Since this does not change over time (?) check whether we already
        # know the answer. If so, return the cached version
        if self._household_id is None:
            self._household_id = self.deviceProperties.GetHouseholdID()[
                'CurrentHouseholdID']
        return self._household_id