php post CSRF verification failed. Request aborted. code example

Example: CSRF verification failed. Request aborted.

<form id='formulario2' method='post' action='>
      <h3>Enter:</h3>
      {% csrf_token %}


     <input id="id_mesaje" name="mesaje" type="email" placeholder="E-mail"/>
    <input type='submit' name="boton2" value='Suscribete' style="display:inline-block;background-color: #80e174; "/>
 </form>