WP SimplePie Change Feed Cache Time

/*Change the cache time of the WP simplepie from the default 12 hours */
function cache_time($seconds)
{
    // change the default feed cache recreation period to 1 hour
    return 3600;
}
add_filter( 'wp_feed_cache_transient_lifetime' , 'cache_time' );


/****
Rest of script starts here:
Visit http://www.worldoweb.co.uk/2012/display-wordpress-posts-on-another-wp-blog
****/
$rss = fetch_feed('http://www.worldoweb.co.uk/feed');