# models.py
class UserModel(AbstractUser):
    photo = models.FileField(upload_to=get_upload_dir,
                             validators=[validators.photo_technicien_validator, ],
                             null=True, blank=True, )
    description = models.CharField(max_length=2048, null=True, )

# views.py
class UserMod(generic_views.UpdateView):
    template_name = 'users/user_edit.html'
    form_class = forms.UserAdminForm
    model = models.UserModel

# forms.py
class UserAdminForm(forms.ModelForm):
    class Meta:
        model = models.UserModel
        fields = ('username', 'description', 'photo')

# validators.py
def photo_technicien_validator(value):
    from Online import constants

    import pdb
    pdb.set_trace()

    logger.info('value: {}'.format(value))
    logger.info('run photo technicien')
    raise forms.ValidationError(
        _('photo invalid')
    )