def METHOD_NAME(self):
    # Auto-purge
    if self.preferences['is_automatic'] is True and \
            self.is_automatic is False:
        self.is_automatic = True
        # Run the first iteration immediately and schedule next iteration
        self.add_untouched_tag()
    elif self.preferences['is_automatic'] is False and \
            self.is_automatic is True:
        self.cancel_autopurge()
        self.is_automatic = False