Sort users by last name and then first name

jmw-sort-users.php

<?php

function nm2_people_page() {

	// Get all user IDs
	$args = array(
		'fields' => 'ID',
	);
	$pids = get_users( $args );

	// If we have people get their first names and last names
	if( $pids ) {
		foreach( $pids as $pid ) {
			$lastnames[] = get_user_meta( $pid, 'last_name', true);
			$firstnames[] = get_user_meta( $pid, 'first_name', true);
		}
	        // Sort arrays by lastname, then firstname then ID
	        array_multisort( $lastnames, $firstnames, $pids );

	        // Print out the results
	        foreach( $pids as $key=>$pid ) {
		       echo $lastnames[ $key ] . ' ' . $firstnames[ $key ] . ' ' . $pid . '<br />';
	        }
	}

}