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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 receive_request(self, transaction):
 """ checks the cache for a response to the request :param transaction: :return: """


        transaction.cached_element = self.cache.search_response(transaction.request)
        if transaction.cached_element is None:
            transaction.cacheHit = False
        else:
            transaction.response = transaction.cached_element.cached_response
            transaction.response.mid = transaction.request.mid
            transaction.cacheHit = True

            age = transaction.cached_element.creation_time + transaction.cached_element.max_age - time.time()
            if transaction.cached_element.freshness is True:
                if age <= 0:
                    logger.debug("resource not fresh")
                    """
                    if the resource is not fresh, its Etag must be added to the request so that the server might validate it instead of sending a new one
                    """
                    transaction.cached_element.freshness = False
                    """
                    ensuring that the request goes to the server
                    """
                    transaction.cacheHit = False
                    logger.debug("requesting etag %s", transaction.response.etag)
                    transaction.request.etag = transaction.response.etag
                else:
                    transaction.response.max_age = age
            else:
                transaction.cacheHit = False
        return transaction