title: Invalid block tag 'set', expected 'empty' or 'endfor'. Did you forget to register or load this tag?
body: <p>I work on Django 1.11 and in my template file I've got this code :</p>
  
  <pre><code>{% for article in all_articles %}
      {% set color_category = 'light-blue' %}
      {% if article.category == 'SEO' %}
          {% color_category = 'light-blue' %}
      {% elif article.category == 'SEA' %}
          {% color_category = 'amber' %}
      {% elif article.category == 'Python' %}
          {% color_category = 'green' %}
      {% elif article.category == 'Django' %}
          {% color_category = 'light-green' %}
      {% else %}
          {% color_category = 'light-blue' %}
      {% endif %}
  {% endfor %}
  </code></pre>
  
  <p>And Django returned me this error :</p>
  
  <pre><code>Exception Type: TemplateSyntaxError
  Exception Value:    
  Invalid block tag on line 12: 'set', expected 'empty' or 'endfor'. Did you forget to register or load this tag?
  </code></pre>
  
  <p>Have you got an idea ?
  Ask if you need more info (like my settings file).</p>
  
  <p>Thanks !</p>