$cached_modified = gmdate('r', strtotime($_SERVER['HTTP_IF_MODIFIED_SINCE']));
$cached_etag = str_replace(['"', "-gzip"], ['', ''],
stripslashes($_SERVER['HTTP_IF_NONE_MATCH']));
$cached_modified = gmdate('r', strtotime($_SERVER['HTTP_IF_MODIFIED_SINCE']));
$cached_etag = str_replace(['"', "-gzip"], ['', ''],
stripslashes($_SERVER['HTTP_IF_NONE_MATCH']));