title: django regroup with duplicate nametuple
body: <p>I have code for regroup in django template, like below:</p>
  <pre><code>        {% regroup clients by title.0 as clients_list %}
            {% for client in clients_list %}
              {{ client.grouper }}
                {% for item in client.list %}
                    {% if item.client_link %}
                          &lt;a href=&quot;{{ item.client_link }}&quot;&gt;{{ item.title }}&lt;/a&gt; 
                    {% else %}
                          {{ item.title }}
                    {% endif %}
                {% endfor %}
            {% endfor %}
  </code></pre>
  <p>Sometime I have duplicate nametuple in my results for the same letter, for example - 'd':</p>
  <pre><code>GroupedResult(grouper='d', list=[&lt;Client: decompany_1&gt;]) GroupedResult(grouper='d', list=[&lt;Client: decompany_2&gt;])
  
  </code></pre>
  <p>so in result I have two headers with letter 'd'</p>
  <p>Someone know, how to avoid this?</p>
  <p><strong>edit</strong>
  views.py</p>
  <pre><code>class ClientsListView(ListView):
      model = Client
      template_name = 'clients/clients_list.html'
      context_object_name = 'clients'
  </code></pre>