How to use the httplib2.__init__.Response function in httplib2

merged_response._stale_digest = response._stale_digest
                    _updateCache(headers, merged_response, content, self.cache, cachekey)
                    response = merged_response
                    response.status = 200
                    response.fromcache = True

                elif response.status == 200:
                    content = new_content
                else:
                    self.cache.delete(cachekey)
                    content = new_content
            else:
                cc = _parse_cache_control(headers)
                if cc.has_key('only-if-cached'):
                    info['status'] = '504'
                    response = Response(info)
                    content = ""
                else:
                    (response, content) = self._request(conn, authority, uri, request_uri, method, body, headers, redirections, cachekey)
        except Exception, e:
            if self.force_exception_to_status_code:
                if isinstance(e, HttpLib2ErrorWithResponse):
                    response = e.response
                    content = e.content
                    response.status = 500
                    response.reason = str(e)
                elif isinstance(e, socket.timeout):
                    content = "Request Timeout"
                    response = Response( {
                            "content-type": "text/plain",
                            "status": "408",
                            "content-length": len(content)

else:
                    # Determine our course of action:
                    #   Is the cached entry fresh or stale?
                    #   Has the client requested a non-cached response?
                    #
                    # There seems to be three possible answers:
                    # 1. [FRESH] Return the cache entry w/o doing a GET
                    # 2. [STALE] Do the GET (but add in cache validators if available)
                    # 3. [TRANSPARENT] Do a GET w/o any cache validators (Cache-Control: no-cache) on the request
                    entry_disposition = _entry_disposition(info, headers)

                    if entry_disposition == "FRESH":
                        if not cached_value:
                            info['status'] = '504'
                            content = ""
                        response = Response(info)
                        if cached_value:
                            response.fromcache = True
                        return (response, content)

                    if entry_disposition == "STALE":
                        if info.has_key('etag') and not self.ignore_etag and not 'if-none-match' in headers:
                            headers['if-none-match'] = info['etag']
                        if info.has_key('last-modified') and not 'last-modified' in headers:
                            headers['if-modified-since'] = info['last-modified']
                    elif entry_disposition == "TRANSPARENT":
                        pass

                    (response, new_content) = self._request(conn, authority, uri, request_uri, method, body, headers, redirections, cachekey)

                if response.status == 304 and method == "GET":
                    # Rewrite the cache entry with the new end-to-end headers

if info.has_key('last-modified') and not 'last-modified' in headers:
                            headers['if-modified-since'] = info['last-modified']
                    elif entry_disposition == "TRANSPARENT":
                        pass

                    (response, new_content) = self._request(conn, authority, uri, request_uri, method, body, headers, redirections, cachekey)

                if response.status == 304 and method == "GET":
                    # Rewrite the cache entry with the new end-to-end headers
                    # Take all headers that are in response
                    # and overwrite their values in info.
                    # unless they are hop-by-hop, or are listed in the connection header.

                    for key in _get_end2end_headers(response):
                        info[key] = response[key]
                    merged_response = Response(info)
                    if hasattr(response, "_stale_digest"):
                        merged_response._stale_digest = response._stale_digest
                    _updateCache(headers, merged_response, content, self.cache, cachekey)
                    response = merged_response
                    response.status = 200
                    response.fromcache = True

                elif response.status == 200:
                    content = new_content
                else:
                    self.cache.delete(cachekey)
                    content = new_content
            else:
                cc = _parse_cache_control(headers)
                if cc.has_key('only-if-cached'):
                    info['status'] = '504'

try:
                response = conn.getresponse()
            except (socket.error, httplib.HTTPException):
                if i == 0:
                    conn.close()
                    conn.connect()
                    continue
                else:
                    raise
            else:
                content = ""
                if method == "HEAD":
                    response.close()
                else:
                    content = response.read()
                response = Response(response)
                if method != "HEAD":
                    content = _decompressContent(response, content)
            break
        return (response, content)

merged_response._stale_digest = response._stale_digest
                    _updateCache(headers, merged_response, content, self.cache, cachekey)
                    response = merged_response
                    response.status = 200
                    response.fromcache = True

                elif response.status == 200:
                    content = new_content
                else:
                    self.cache.delete(cachekey)
                    content = new_content
            else:
                cc = _parse_cache_control(headers)
                if cc.has_key('only-if-cached'):
                    info['status'] = '504'
                    response = Response(info)
                    content = ""
                else:
                    (response, content) = self._request(conn, authority, uri, request_uri, method, body, headers, redirections, cachekey)
        except Exception, e:
            if self.force_exception_to_status_code:
                if isinstance(e, HttpLib2ErrorWithResponse):
                    response = e.response
                    content = e.content
                    response.status = 500
                    response.reason = str(e)
                elif isinstance(e, socket.timeout):
                    content = "Request Timeout"
                    response = Response( {
                            "content-type": "text/plain",
                            "status": "408",
                            "content-length": len(content)

merged_response._stale_digest = response._stale_digest
                    _updateCache(headers, merged_response, content, self.cache, cachekey)
                    response = merged_response
                    response.status = 200
                    response.fromcache = True

                elif response.status == 200:
                    content = new_content
                else:
                    self.cache.delete(cachekey)
                    content = new_content
            else:
                cc = _parse_cache_control(headers)
                if cc.has_key('only-if-cached'):
                    info['status'] = '504'
                    response = Response(info)
                    content = ""
                else:
                    (response, content) = self._request(conn, authority, uri, request_uri, method, body, headers, redirections, cachekey)
        except Exception, e:
            if self.force_exception_to_status_code:
                if isinstance(e, HttpLib2ErrorWithResponse):
                    response = e.response
                    content = e.content
                    response.status = 500
                    response.reason = str(e)
                elif isinstance(e, socket.timeout):
                    content = "Request Timeout"
                    response = Response( {
                            "content-type": "text/plain",
                            "status": "408",
                            "content-length": len(content)

merged_response._stale_digest = response._stale_digest
                    _updateCache(headers, merged_response, content, self.cache, cachekey)
                    response = merged_response
                    response.status = 200
                    response.fromcache = True

                elif response.status == 200:
                    content = new_content
                else:
                    self.cache.delete(cachekey)
                    content = new_content
            else:
                cc = _parse_cache_control(headers)
                if 'only-if-cached'in cc:
                    info['status'] = '504'
                    response = Response(info)
                    content = b""
                else:
                    (response, content) = self._request(conn, authority, uri, request_uri, method, body, headers, redirections, cachekey)
        except Exception as e:
            if self.force_exception_to_status_code:
                if isinstance(e, HttpLib2ErrorWithResponse):
                    response = e.response
                    content = e.content
                    response.status = 500
                    response.reason = str(e)
                elif isinstance(e, socket.timeout):
                    content = b"Request Timeout"
                    response = Response({
                        "content-type": "text/plain",
                        "status": "408",
                        "content-length": len(content)

try:
                response = conn.getresponse()
            except (socket.error, httplib.HTTPException):
                if i < RETRIES-1:
                    conn.close()
                    conn.connect()
                    continue
                else:
                    raise
            else:
                content = ""
                if method == "HEAD":
                    conn.close()
                else:
                    content = response.read()
                response = Response(response)
                if method != "HEAD":
                    content = _decompressContent(response, content)
            break
        return (response, content)

if 'only-if-cached'in cc:
                    info['status'] = '504'
                    response = Response(info)
                    content = b""
                else:
                    (response, content) = self._request(conn, authority, uri, request_uri, method, body, headers, redirections, cachekey)
        except Exception as e:
            if self.force_exception_to_status_code:
                if isinstance(e, HttpLib2ErrorWithResponse):
                    response = e.response
                    content = e.content
                    response.status = 500
                    response.reason = str(e)
                elif isinstance(e, socket.timeout):
                    content = b"Request Timeout"
                    response = Response({
                        "content-type": "text/plain",
                        "status": "408",
                        "content-length": len(content)
                    })
                    response.reason = "Request Timeout"
                else:
                    content = str(e).encode('utf-8')
                    response = Response({
                        "content-type": "text/plain",
                        "status": "400",
                        "content-length": len(content)
                    })
                    response.reason = "Bad Request"
            else:
                raise

merged_response._stale_digest = response._stale_digest
                    _updateCache(headers, merged_response, content, self.cache, cachekey)
                    response = merged_response
                    response.status = 200
                    response.fromcache = True

                elif response.status == 200:
                    content = new_content
                else:
                    self.cache.delete(cachekey)
                    content = new_content
            else:
                cc = _parse_cache_control(headers)
                if cc.has_key('only-if-cached'):
                    info['status'] = '504'
                    response = Response(info)
                    content = ""
                else:
                    (response, content) = self._request(conn, authority, uri, request_uri, method, body, headers, redirections, cachekey)
        except Exception, e:
            if self.force_exception_to_status_code:
                if isinstance(e, HttpLib2ErrorWithResponse):
                    response = e.response
                    content = e.content
                    response.status = 500
                    response.reason = str(e)
                elif isinstance(e, socket.timeout):
                    content = "Request Timeout"
                    response = Response( {
                            "content-type": "text/plain",
                            "status": "408",
                            "content-length": len(content)