This is a callback that is registered to be called periodically
        from the legion.  The legion chooses when it might be called,
        typically when it is otherwise idle.

def _task_periodic(self):
        """
        This is a callback that is registered to be called periodically
        from the legion.  The legion chooses when it might be called,
        typically when it is otherwise idle.
    """
        log = self._params.get('log', self._discard)
        log.debug("periodic")
        self.manage()