class Meta(BaseRegistrationForm.Meta): model = User fields = [ User.get_email_field_name(), 'password1', 'password2' ]
def validate_unique(self): exclude = self._get_validation_exclusions() exclude.remove('site') exclude.remove('festival') self.instance.site = self.site self.instance.festival = self.festival try: self.instance.validate_unique(exclude) except ValidationError: self._update_errors(ValidationError({User.get_email_field_name(): 'A user with that e-mail already exists.'}))