title: Django - Unable to lookup 'u'
body: <p>yesterday everything was working perfect, today i enter to the admin and this error is showing when i click in "usuarios_aux" model...</p>
  
  <p><code>Unable to lookup 'u' on Usuario_aux or Usuario_AuxAdmin</code></p>
  
  <p>Why is this happening? heres the traceback.</p>
  
  <blockquote>
    <p>Environment:</p>
    
    <p>Request Method: GET Request URL:
    <a href="http://provisional.jetint.webfactional.com/admin/clients/usuario_aux/" rel="nofollow">http://provisional.jetint.webfactional.com/admin/clients/usuario_aux/</a></p>
    
    <p>Django Version: 1.7.3 Python Version: 2.7.9 Installed Applications:
    ('django.contrib.admin.apps.SimpleAdminConfig', 
    'django.contrib.auth',  'django.contrib.contenttypes', 
    'django.contrib.sessions',  'django.contrib.messages', 
    'django.contrib.staticfiles',  'adminplus',  'clients',  'currier')
    Installed Middleware:
    ('django.contrib.sessions.middleware.SessionMiddleware', 
    'django.middleware.common.CommonMiddleware', 
    'django.middleware.csrf.CsrfViewMiddleware', 
    'django.contrib.auth.middleware.AuthenticationMiddleware', 
    'django.contrib.messages.middleware.MessageMiddleware', 
    'django.middleware.clickjacking.XFrameOptionsMiddleware')</p>
    
    <p>Template error: In template
    /home/jetint/webapps/jet_test/lib/python2.7/Django-1.7.3-py2.7.egg/django/contrib/admin/templates/admin/change_list.html, error at line 91    Unable to lookup 'u' on Usuario_aux or
    Usuario_AuxAdmin    81 :         {% endif %}</p>
    
    <p>82 :       {% endblock %}</p>
    
    <p>83 : </p>
    
    <p>84 :       {% csrf_token %}</p>
    
    <p>85 :       {% if cl.formset %}</p>
    
    <p>86 :         {{ cl.formset.management_form }}</p>
    
    <p>87 :       {% endif %}</p>
    
    <p>88 : </p>
    
    <p>89 :       {% block result_list %}</p>
    
    <p>90 :           {% if action_form and actions_on_top and
    cl.full_result_count %}{% admin_actions %}{% endif %}</p>
    
    <p>91 :            {% result_list cl %} </p>
    
    <p>92 :           {% if action_form and actions_on_bottom and
    cl.full_result_count %}{% admin_actions %}{% endif %}</p>
    
    <p>93 :       {% endblock %}</p>
    
    <p>94 :       {% block pagination %}{% pagination cl %}{% endblock %}</p>
    
    <p>95 :       </p>
    
    <p>96 :     </p>
    
    <p>97 :   </p>
    
    <p>98 : {% endblock %}</p>
    
    <p>99 : </p>
    
    <p>Traceback: File
    "/home/jetint/webapps/jet_test/lib/python2.7/Django-1.7.3-py2.7.egg/django/core/handlers/base.py"
    in get_response
      137.                 response = response.render() File "/home/jetint/webapps/jet_test/lib/python2.7/Django-1.7.3-py2.7.egg/django/template/response.py"
    in render
      103.             self.content = self.rendered_content File "/home/jetint/webapps/jet_test/lib/python2.7/Django-1.7.3-py2.7.egg/django/template/response.py"
    in rendered_content
      80.         content = template.render(context) File "/home/jetint/webapps/jet_test/lib/python2.7/Django-1.7.3-py2.7.egg/django/template/base.py"
    in render
      148.             return self._render(context) File "/home/jetint/webapps/jet_test/lib/python2.7/Django-1.7.3-py2.7.egg/django/template/base.py"
    in _render
      142.         return self.nodelist.render(context) File "/home/jetint/webapps/jet_test/lib/python2.7/Django-1.7.3-py2.7.egg/django/template/base.py"
    in render
      844.                 bit = self.render_node(node, context) File "/home/jetint/webapps/jet_test/lib/python2.7/Django-1.7.3-py2.7.egg/django/template/debug.py"
    in render_node
      80.             return node.render(context) File "/home/jetint/webapps/jet_test/lib/python2.7/Django-1.7.3-py2.7.egg/django/template/loader_tags.py"
    in render
      126.         return compiled_parent._render(context) File "/home/jetint/webapps/jet_test/lib/python2.7/Django-1.7.3-py2.7.egg/django/template/base.py"
    in _render
      142.         return self.nodelist.render(context) File "/home/jetint/webapps/jet_test/lib/python2.7/Django-1.7.3-py2.7.egg/django/template/base.py"
    in render
      844.                 bit = self.render_node(node, context) File "/home/jetint/webapps/jet_test/lib/python2.7/Django-1.7.3-py2.7.egg/django/template/debug.py"
    in render_node
      80.             return node.render(context) File "/home/jetint/webapps/jet_test/lib/python2.7/Django-1.7.3-py2.7.egg/django/template/loader_tags.py"
    in render
      126.         return compiled_parent._render(context) File "/home/jetint/webapps/jet_test/lib/python2.7/Django-1.7.3-py2.7.egg/django/template/base.py"
    in _render
      142.         return self.nodelist.render(context) File "/home/jetint/webapps/jet_test/lib/python2.7/Django-1.7.3-py2.7.egg/django/template/base.py"
    in render
      844.                 bit = self.render_node(node, context) File "/home/jetint/webapps/jet_test/lib/python2.7/Django-1.7.3-py2.7.egg/django/template/debug.py"
    in render_node
      80.             return node.render(context) File "/home/jetint/webapps/jet_test/lib/python2.7/Django-1.7.3-py2.7.egg/django/template/loader_tags.py"
    in render
      65.                 result = block.nodelist.render(context) File "/home/jetint/webapps/jet_test/lib/python2.7/Django-1.7.3-py2.7.egg/django/template/base.py"
    in render
      844.                 bit = self.render_node(node, context) File "/home/jetint/webapps/jet_test/lib/python2.7/Django-1.7.3-py2.7.egg/django/template/debug.py"
    in render_node
      80.             return node.render(context) File "/home/jetint/webapps/jet_test/lib/python2.7/Django-1.7.3-py2.7.egg/django/template/loader_tags.py"
    in render
      65.                 result = block.nodelist.render(context) File "/home/jetint/webapps/jet_test/lib/python2.7/Django-1.7.3-py2.7.egg/django/template/base.py"
    in render
      844.                 bit = self.render_node(node, context) File "/home/jetint/webapps/jet_test/lib/python2.7/Django-1.7.3-py2.7.egg/django/template/debug.py"
    in render_node
      80.             return node.render(context) File "/home/jetint/webapps/jet_test/lib/python2.7/Django-1.7.3-py2.7.egg/django/template/base.py"
    in render
      1207.                     _dict = func(*resolved_args, **resolved_kwargs) File "/home/jetint/webapps/jet_test/lib/python2.7/Django-1.7.3-py2.7.egg/django/contrib/admin/templatetags/admin_list.py"
    in result_list
      307.     headers = list(result_headers(cl)) File "/home/jetint/webapps/jet_test/lib/python2.7/Django-1.7.3-py2.7.egg/django/contrib/admin/templatetags/admin_list.py"
    in result_headers
      101.             return_attr=True File "/home/jetint/webapps/jet_test/lib/python2.7/Django-1.7.3-py2.7.egg/django/contrib/admin/utils.py"
    in label_for_field
      324.                 raise AttributeError(message)</p>
    
    <p>Exception Type: AttributeError at /admin/clients/usuario_aux/
    Exception Value: Unable to lookup 'u' on Usuario_aux or
    Usuario_AuxAdmin</p>
  </blockquote>
  
  <p>how i can fix this?</p>
  
  <p>model: </p>
  
  <pre><code>class Usuario_aux(models.Model):
      user = models.ForeignKey(User)
      clave = models.CharField(max_length=100)
      correo = models.BooleanField(default=False)
  </code></pre>
  
  <p>admin.py:</p>
  
  <pre><code>class Usuario_AuxAdmin(admin.ModelAdmin):
      list_display = ('user', 'correo')
      search_fields = ('user', 'correo')
  admin.site.register(Usuario_aux, Usuario_AuxAdmin)
  </code></pre>