{% with messages = get_flashed_messages() %}
{% if messages %}
<div class="container">
    {% for message in messages %}
    <div class="alert alert-info alert-dismissable">
        <a href="#" class="close" data-dismiss="alert" aria-label="close">×</a>
        {{ message }}
    </div>
    {% endfor %}
</div>
{% endif %}
{% endwith %}