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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_event_type(self_, watcher, event, triggered):
 """ Returns an updated Event object with the type field set appropriately. """

        if triggered:
            event_type = 'triggered'
        else:
            event_type = 'changed' if watcher.onlychanged else 'set'
        return Event(what=event.what, name=event.name, obj=event.obj, cls=event.cls,
                     old=event.old, new=event.new, type=event_type)