Error with https://affiliate.itunes.apple.com/resources/documentation/itunes-store-web-service-search-api/

exception = HTTPSConnectionPool(host='affiliate.itunes.apple.com', port=443): Max retries exceeded with url: /resources/documentation/itunes-store-web-service-search-api/ (Caused by NameResolutionError(": Failed to resolve 'affiliate.itunes.apple.com' ([Errno -2] Name or service not known)"))