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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _update_events(self):
 """Update our cached list of latest activity events."""

        events = self._skybell.dev_cache(self, CONST.EVENT) or {}

        for activity in self._activities:
            event = activity.get(CONST.EVENT)
            created_at = activity.get(CONST.CREATED_AT)

            old_event = events.get(event)

            if old_event and created_at < old_event.get(CONST.CREATED_AT):
                continue
            else:
                events[event] = activity

        self._skybell.update_dev_cache(
            self,
            {
                CONST.EVENT: events
            })