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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 delete_action_cache(self, action_key):
 """Delete action needs and excludes from cache. .. note:: It returns the action if a cache system is defined. :param action_key: The unique action name. """

        if self.cache:
            self.cache.delete(
                self.app.config['ACCESS_ACTION_CACHE_PREFIX'] +
                action_key
            )