WPMU Membership2: Shortcode show all members and memberships

code.php

<?php
/**
 * ShortCode to use: [ms-members-details] 
 */
add_shortcode( 'ms-members-details', 'ms_members_details' );
function ms_members_details()
{
    $html = '<table cellpadding="0" cellspacing="0">';
    $html .= '<tr>';
    $html .= '<td><b>User ID</b></td>';
    $html .= '<td><b>Username</b></td>';
    $html .= '<td><b>Display Name</b></td>';
    $html .= '<td><b>Membership(s)</b></td>';
    $html .= '</tr>';
    $members = MS_Model_Member::get_members();
    foreach( $members as $member )
    {
        $html .= '<tr>';
        $html .= '<td>' . $member->id . '</td>';
        $html .= '<td>' . $member->username . '</td>';
        $html .= '<td>' . $member->name . '</td>';
        
        if( count( $member->subscriptions ) < 1 )
        {
            $html .= '<td>&nbsp;</td>';
        }
        
        $html .= '<td>';
        $temp = array();
        foreach( $member->subscriptions as $subscription )
        {
            $membership = MS_Factory::load( 'MS_Model_Membership', $subscription->membership_id );
            $temp[] = $membership->name;
            $html .= implode( ', ', $temp );
        }
        $html .= '</td>';
        $html .= '</tr>';
    }
    $html .= '</table>';
    
    return $html;
}