Python-сообщество

class AuthUserManager(BaseUserManager):
    def create_user(self, username, email, password=None):
        if not email:
            raise ValueError('User must have email')
        if not username:
            raise ValueError('User must have username')
        user = self.model(username=username, email=self.normalize_email(email))
        user.is_active = True
        user.set_password(password)
        user.save(using=self._db)
        return user
    def create_superuser(self, username, email, password):
        user = self.creat_user(username=username, email=email, password=password)
        user.is_staff = True
        user.is_superuser = True
        user.save(using=self._db)
        return user
class AuthUser(AbstractBaseUser, PermissionsMixin):
    alphanumeric = RegexValidator(r'^[0-9a-zA-Z]*$', message='Only alphanumeric characters are allowed.')
    username = models.CharField(unique=True, max_length=30, validators=[alphanumeric])
    email = models.EmailField(verbose_name='email field', unique=True, max_length=255)
    first_name = models.CharField(max_length=50, null=True, blank=True)
    second_name = models.CharField(max_length=50, null=True, blank=True)
    last_name = models.CharField(max_length=50, null=True, blank=True)
    date_joined = models.DateTimeField(auto_now_add=True)
    is_active = models.BooleanField(default=True, null=False)
    is_staff = models.BooleanField(default=False, null=False)
    # profile_image = models.ImageField(upload_to='uploads', blank=False, default='/static/defaultprofileimage.png')
    user_bio = models.TextField()
    objects = AuthUserManager()
    USERNAME_FIELD = 'username'
    REQUIRED_FIELDS = ['email']
    def get_full_name(self):
        return '%s %s %s' .format(self.last_name, self.first_name, self.second_name)
    def get_short_name(self):
        return self.username
    def __str__(self):
        return self.email

AUTH_USER_MODEL = 'app.models.AuthUser'

class AuthUserCreationForm(UserCreationForm):
    password1 = forms.CharField(label='Password', widget=forms.PasswordInput)
    password2 = forms.CharField(label='Password Confirmation', widget=forms.PasswordInput)
    class Meta(UserCreationForm.Meta):
        model = AuthUser
        fields = ('email', 'username')
    def clean_username(self):
        username = self.clean_data['username']
        try:
            AuthUser._default_managet.get(username=username)
        except Authuser.DoesNotExist:
            return username
        raise forms.ValidationError(self.error_messages['duplicate_username'])
    def clean_password2(self):
        password1 = self.cleaned_data.get('password1')
        password2 = self.cleaned_data.get('password2')
        if password1 and password2 and password1 != password2:
            raise forms.ValidationError('Password do not match.')
        return password2
    def save(self, commit=True):
        user = super(UserCreationForm, self).save(commit=False)
        user.set_password(self.cleaned_data['password1'])
        if commit:
            user.save()
        return user
class AuthUserChangeForm(UserChangeForm):
    password = ReadOnlyPasswordHashField(label='password', help_text='There is no way too see this password.')
    class Meta(UserChangeForm.Meta):
        model = AuthUser
        fields = ('username', 'email', 'password', 'is_active', 'is_staff', 'is_superuser', 'user_permissions')
    def clean_password(self):
        return self.initial['password']
class AuthUserAdmin(UserAdmin):
    form = AuthUserChangeForm
    add_form = AuthUserCreationForm
    list_display = ('username', 'email', 'is_staff', 'is_superuser',)
    list_filter = ('is_superuser')
    fieldsets = (
        (None, {'fields': ('username', 'email', 'password', 'firs_name', 'second_name', 'last_name', 'user_bio')}),
        ('Permissions', {'fields': ('is_active', 'is_superuser', 'is_staff')}),
    )
    add_fieldsets = (
        (None, {
            'classes': ('wide',),
            'fields': ('username', 'email', 'password1', 'password2', 'is_stuff', 'is_superuser')
        })
    )
    search_fields = ('username', 'email')
    ordering = ('email',)
    filter_horizontal = ('groups', 'user_permissions')
admin.site.register(AuthUser, AuthUserAdmin)

Environment:
Request Method: GET
Request URL: http://127.0.0.1:8000/admin/app/authuser/add/
Django Version: 1.8.3
Python Version: 3.4.3
Installed Applications:
('django.contrib.admin',
 'django.contrib.auth',
 'django.contrib.contenttypes',
 'django.contrib.sessions',
 'django.contrib.messages',
 'django.contrib.staticfiles',
 'mainnews',
 'app')
Installed Middleware:
('django.contrib.sessions.middleware.SessionMiddleware',
 'django.middleware.common.CommonMiddleware',
 'django.middleware.csrf.CsrfViewMiddleware',
 'django.contrib.auth.middleware.AuthenticationMiddleware',
 'django.contrib.auth.middleware.SessionAuthenticationMiddleware',
 'django.contrib.messages.middleware.MessageMiddleware',
 'django.middleware.clickjacking.XFrameOptionsMiddleware',
 'django.middleware.security.SecurityMiddleware')
Traceback:
File "C:\Python34\lib\site-packages\django-1.8.3-py3.4.egg\django\core\handlers\base.py" in get_response
  132.                     response = wrapped_callback(request, *callback_args, **callback_kwargs)
File "C:\Python34\lib\site-packages\django-1.8.3-py3.4.egg\django\contrib\admin\options.py" in wrapper
  616.                 return self.admin_site.admin_view(view)(*args, **kwargs)
File "C:\Python34\lib\site-packages\django-1.8.3-py3.4.egg\django\utils\decorators.py" in _wrapped_view
  110.                     response = view_func(request, *args, **kwargs)
File "C:\Python34\lib\site-packages\django-1.8.3-py3.4.egg\django\views\decorators\cache.py" in _wrapped_view_func
  57.         response = view_func(request, *args, **kwargs)
File "C:\Python34\lib\site-packages\django-1.8.3-py3.4.egg\django\contrib\admin\sites.py" in inner
  233.             return view(request, *args, **kwargs)
File "C:\Python34\lib\site-packages\django-1.8.3-py3.4.egg\django\utils\decorators.py" in _wrapper
  34.             return bound_func(*args, **kwargs)
File "C:\Python34\lib\site-packages\django-1.8.3-py3.4.egg\django\views\decorators\debug.py" in sensitive_post_parameters_wrapper
  76.             return view(request, *args, **kwargs)
File "C:\Python34\lib\site-packages\django-1.8.3-py3.4.egg\django\utils\decorators.py" in bound_func
  30.                 return func.__get__(self, type(self))(*args2, **kwargs2)
File "C:\Python34\lib\site-packages\django-1.8.3-py3.4.egg\django\utils\decorators.py" in _wrapper
  34.             return bound_func(*args, **kwargs)
File "C:\Python34\lib\site-packages\django-1.8.3-py3.4.egg\django\utils\decorators.py" in _wrapped_view
  110.                     response = view_func(request, *args, **kwargs)
File "C:\Python34\lib\site-packages\django-1.8.3-py3.4.egg\django\utils\decorators.py" in bound_func
  30.                 return func.__get__(self, type(self))(*args2, **kwargs2)
File "C:\Python34\lib\contextlib.py" in inner
  30.                [b] return func(*args, **kwds)[/b]
File "C:\Python34\lib\site-packages\django-1.8.3-py3.4.egg\django\contrib\auth\admin.py" in add_view
  121.                                                extra_context)
File "C:\Python34\lib\site-packages\django-1.8.3-py3.4.egg\django\contrib\admin\options.py" in add_view
  1516.         return self.changeform_view(request, None, form_url, extra_context)
File "C:\Python34\lib\site-packages\django-1.8.3-py3.4.egg\django\utils\decorators.py" in _wrapper
  34.             return bound_func(*args, **kwargs)
File "C:\Python34\lib\site-packages\django-1.8.3-py3.4.egg\django\utils\decorators.py" in _wrapped_view
  110.                     response = view_func(request, *args, **kwargs)
File "C:\Python34\lib\site-packages\django-1.8.3-py3.4.egg\django\utils\decorators.py" in bound_func
  30.                 return func.__get__(self, type(self))(*args2, **kwargs2)
File "C:\Python34\lib\contextlib.py" in inner
  30.                 [b]return func(*args, **kwds)[/b]
File "C:\Python34\lib\site-packages\django-1.8.3-py3.4.egg\django\contrib\admin\options.py" in changeform_view
  1456.         ModelForm = self.get_form(request, obj)
File "C:\Python34\lib\site-packages\django-1.8.3-py3.4.egg\django\contrib\auth\admin.py" in get_form
  79.         return super(UserAdmin, self).get_form(request, obj, **defaults)
File "C:\Python34\lib\site-packages\django-1.8.3-py3.4.egg\django\contrib\admin\options.py" in get_form
  675.             fields = flatten_fieldsets(self.get_fieldsets(request, obj))
File "C:\Python34\lib\site-packages\django-1.8.3-py3.4.egg\django\contrib\admin\utils.py" in flatten_fieldsets
  101.     for name, opts in fieldsets:
Exception Type: TypeError at /admin/app/authuser/add/
Exception Value: 'NoneType' object is not iterable