title: AttributeError: 'User' object has no attribute 'check_password' error in Django?
body: <p>I have a custom model with which I am trying to authenticate:</p>
  
  <pre><code>class User(models.Model):
      #id = models.IntegerField(primary_key=True)
      #identifier = models.CharField(max_length=40, unique=True, db_index=True)
      username = models.CharField(max_length=90, unique=True, db_index=True)
      create_time = models.DateTimeField(null=True, blank=True)
      update_time = models.DateTimeField(null=True, blank=True)
      email = models.CharField(max_length=225)
      password = models.CharField(max_length=120)
      external = models.IntegerField(null=True, blank=True)
      deleted = models.IntegerField(null=True, blank=True)
      purged = models.IntegerField(null=True, blank=True)
      form_values_id = models.IntegerField(null=True, blank=True)
      disk_usage = models.DecimalField(null=True, max_digits=16, decimal_places=0, blank=True)
      #last_login = models.DateTimeField()
  
      objects = UserManager()
      USERNAME_FIELD = 'username'
      #check_password(password)
      class Meta:
          db_table = u'galaxy_user'
  </code></pre>
  
  <p>I have mentioned this in `settings.</p>
  
  <p>AUTH_USER_MODEL = 'fileupload.user'</p>
  
  <pre><code> #views.py
          def login_backend(request):
              if request.method == 'POST':
                  username = request.POST['username']
                  password = request.POST['password']
                  user = authenticate(username=username, password=password)
                  if user is not None:
                      login(request, user)
                      return HttpResponseRedirect('/overview/')
                  else:
                      return HttpResponseRedirect('/login_backend/')
              else:
                  return render_to_response('login_backend.html', context_instance=RequestContext(request))
  </code></pre>
  
  <p>However I am getting this error:</p>
  
  <pre><code>AttributeError: 'User' object has no attribute 'check_password' error 
  </code></pre>
  
  <p>What am I doing wrong?</p>