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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 handle_event(self, event):
 """ Send the event to the subclass or simply reject """

        subscription_id = event.subscription_id
        if subscription_id in self._subscriptions:
            # FIXME: [1] should be a constant
            handler = self._subscriptions[subscription_id][SUBSCRIPTION_CALLBACK]
            WampSubscriptionWrapper(self,handler,event).start()