paste/paste/templates/home.html.j2

<form id="paste-content" method="POST" accept-charset="UTF-8" action="{{ url_for('home.create') }}">
     <textarea name="content" form="paste-content">Enter text here...</textarea>
    <label for="time">Time in second</label>
    <input id="time" name="time">
    <input type="submit">
</form>
{% with messages = get_flashed_messages() %}
    {% if messages %}
        <p>Paste available at : <a href="{{ messages[0] }}">{{ messages[0] }}</a></p>
    {% endif %}
{% endwith %}