title: Jinja Invalid Filter, filter is built in
body: <p>I have read through the Jinja documentation and am using the <code>truncate</code> filter. I have used it exactly as defined in the documentation. </p>
  
  <p>From the docs:</p>
  
  <blockquote>
    <p>truncate(s, length=255, killwords=False, end=’…’, leeway=None) 
    Return a truncated copy of the string. The length is specified with the first
    parameter which defaults to 255. If the second parameter is true the
    filter will cut the text at length. Otherwise it will discard the last
    word. If the text was in fact truncated it will append an ellipsis
    sign ("..."). If you want a different ellipsis sign than "..." you can
    specify it using the third parameter. Strings that only exceed the
    length by the tolerance margin given in the fourth parameter will not
    be truncated.</p>
  </blockquote>
  
  <p>Here is my code:</p>
  
  <pre><code>{% if post.replies.all %}
  &lt;ul class="accordion" data-accordion data-multi-Expand="true" data-allow-all-closed="true"&gt;
  {% for reply in post.replies.all %}
          &lt;li class="accordion-item" data-accordion&gt;
              &lt;a href="#" class="accordion-title"&gt;{{reply.by}}: {{reply.content|truncate(14)}}&lt;/a&gt;
              &lt;div class="accordion-content" data-tab-content&gt;
                  &lt;img src="{{ reply.by.profile.img_url }}" class="thumbnail" width="50" height="50"&gt;
                  &lt;p&gt;{{ reply.content }}&lt;/p&gt;
              &lt;/div&gt;
          &lt;/li&gt;
  {% endfor %}
  &lt;/ul&gt;
  {% endif %}
  </code></pre>
  
  <p>I get the following traceback after testing:</p>
  
  <p><a href="https://i.stack.imgur.com/peXu8.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/peXu8.png" alt="enter image description here"></a></p>
  
  <p>What am I doing wrong?</p>