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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:
 async def process_response(self, request, response):
 """Called to perform any processing of the response required. This function stores any cookie data in the COOKIE_AUTH_KEY as a cookie in the response object. If the value is a empty string, the associated cookie is deleted instead. This function requires the response to be a aiohttp Response object, and assumes that the response has not started if the remember or forget functions are called during the request. Args: request: aiohttp Request object. response: response object returned from the handled view Raises: RuntimeError: Raised if response has already started. """

        await super().process_response(request, response)
        if COOKIE_AUTH_KEY in request:
            if response.started:
                raise RuntimeError("Cannot save cookie into started response")

            cookie = request[COOKIE_AUTH_KEY]
            if cookie == '':
                response.del_cookie(self.cookie_name)
            else:
                response.set_cookie(self.cookie_name, cookie)