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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 _action_enabled(self, event, action):
 """Check if an action for a notification is enabled."""

        event_actions = self._aconfig.get(event)
        if event_actions is None:
            return True
        if event_actions is False:
            return False
        return action in event_actions