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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 cached_request(self, request):
 """ Return a cached response if it exists in the cache, otherwise return False. """

        cache_url = self.cache_url(request.url)
        logger.debug('Looking up "%s" in the cache', cache_url)
        cc = self.parse_cache_control(request.headers)

        # Bail out if the request insists on fresh data
        if "no-cache" in cc:
            logger.debug('Request header has "no-cache", cache bypassed')
            return False

        if "max-age" in cc and cc["max-age"] == 0:
            logger.debug('Request header has "max_age" as 0, cache bypassed')
            return False

        # Request allows serving from the cache, let's see if we find something
        cache_data = self.cache.get(cache_url)
        if cache_data is None:
            logger.debug("No cache entry available")
            return False

        # Check whether it can be deserialized
        resp = self.serializer.loads(request, cache_data)
        if not resp:
            logger.warning("Cache entry deserialization failed, entry ignored")
            return False

        # If we have a cached 301, return it immediately. We don't
        # need to test our response for other headers b/c it is
        # intrinsically "cacheable" as it is Permanent.
        # See:
        #   https://tools.ietf.org/html/rfc7231#section-6.4.2
        #
        # Client can try to refresh the value by repeating the request
        # with cache busting headers as usual (ie no-cache).
        if resp.status == 301:
            msg = (
                'Returning cached "301 Moved Permanently" response '
                "(ignoring date and etag information)"
            )
            logger.debug(msg)
            return resp

        headers = CaseInsensitiveDict(resp.headers)
        if not headers or "date" not in headers:
            if "etag" not in headers:
                # Without date or etag, the cached response can never be used
                # and should be deleted.
                logger.debug("Purging cached response: no date or etag")
                self.cache.delete(cache_url)
            logger.debug("Ignoring cached response: no date")
            return False

        now = time.time()
        date = calendar.timegm(parsedate_tz(headers["date"]))
        current_age = max(0, now - date)
        logger.debug("Current age based on date: %i", current_age)

        # TODO: There is an assumption that the result will be a
        #       urllib3 response object. This may not be best since we
        #       could probably avoid instantiating or constructing the
        #       response until we know we need it.
        resp_cc = self.parse_cache_control(headers)

        # determine freshness
        freshness_lifetime = 0

        # Check the max-age pragma in the cache control header
        if "max-age" in resp_cc:
            freshness_lifetime = resp_cc["max-age"]
            logger.debug("Freshness lifetime from max-age: %i", freshness_lifetime)

        # If there isn't a max-age, check for an expires header
        elif "expires" in headers:
            expires = parsedate_tz(headers["expires"])
            if expires is not None:
                expire_time = calendar.timegm(expires) - date
                freshness_lifetime = max(0, expire_time)
                logger.debug("Freshness lifetime from expires: %i", freshness_lifetime)

        # Determine if we are setting freshness limit in the
        # request. Note, this overrides what was in the response.
        if "max-age" in cc:
            freshness_lifetime = cc["max-age"]
            logger.debug(
                "Freshness lifetime from request max-age: %i", freshness_lifetime
            )

        if "min-fresh" in cc:
            min_fresh = cc["min-fresh"]
            # adjust our current age by our min fresh
            current_age += min_fresh
            logger.debug("Adjusted current age from min-fresh: %i", current_age)

        # Return entry if it is fresh enough
        if freshness_lifetime > current_age:
            logger.debug('The response is "fresh", returning cached response')
            logger.debug("%i > %i", freshness_lifetime, current_age)
            return resp

        # we're not fresh. If we don't have an Etag, clear it out
        if "etag" not in headers:
            logger.debug('The cached response is "stale" with no etag, purging')
            self.cache.delete(cache_url)

        # return the original handler
        return False