Remove core updates notice in WordPress

functions.php

function remove_core_updates(){
    global $wp_version;return(object) array('last_checked'=> time(),'version_checked'=> $wp_version,);
}

add_filter('pre_site_transient_update_core','remove_core_updates');
add_filter('pre_site_transient_update_plugins','remove_core_updates');
add_filter('pre_site_transient_update_themes','remove_core_updates');