def next_future_periodic_delta(self) -> Optional[float]:
        """Give the amount of seconds before the next periodic task is due."""
        try:
            next_event = self._scheduler.queue[0]
        except IndexError:
            return None

        now = time.monotonic()
        next_event_time = next_event[0]
        if next_event_time < now:
            return 0

        return next_event_time - now
def next_future_periodic_delta ( self ) -> Optional [ float ] : try : next_event = self . _scheduler . queue [ 0 ] except IndexError : return None now = time . monotonic ( ) next_event_time = next_event [ 0 ] if next_event_time < now : return 0 return next_event_time - now
Give the amount of seconds before the next periodic task is due.