//------------------------------------------------//
// Display the last editor of a post
//------------------------------------------------//
$post_ID = get_the_ID(); 
if ( $last_id = get_post_meta($post_ID, '_edit_last', true) ) {
 $last_user = get_userdata($last_id);
 printf(__('Last edited by %1$s on %2$s at %3$s'), wp_specialchars( $last_user->display_name ), mysql2date(get_option('date_format'), $post->post_modified), mysql2date(get_option('time_format'), 
$post->post_modified));
};