$def with (active_tab)
<div id="admin_toolbar" class="panel" style="width:98%;text-align:left">
$for id, title, url in admin_pages:
    <a
    $if id == active_tab:
         class="tab_button_active"
    $else:
        class="tab_button"
    href='$base$url'>$title</a>
</div>
