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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 after_request(self, fn):
 """ Register a function to be run after each request. Your function must take one parameter, an instance of :attr:`response_class` and return a new response object or the same (see :meth:`process_response`). As of Flask 0.7 this function might not be executed at the end of the request in case an unhandled exception occurred. """

        self._defer(lambda app: app.after_request(fn))
        return fn