python - Is there another way to change the error message on a ModelForm for a validate_unique error? -

disregarding actual method use below parsing error messages since needs lots of improvement make more general-purpose, parsing error messages raised way of changing error message displayed?

specifically, i've removed 1 of fields modelform. when validate_unique run remove field validation described in this answer on so. error message django displays on form when validate_unique run says: 'x y , z exists.' z field manually removed modelform. want change error message because mentioning z, not-displayed field, confusing user has no way of changing z on form.

this feels fragile , hacky.

def validate_unique(self):     exclude = self._get_validation_exclusions()     exclude.remove('a_field_not_shown_on_form')      try:         self.instance.validate_unique(exclude=exclude)     except validationerror, e:         if '__all__' in e.message_dict:             idx, err in enumerate(e.message_dict['__all__']):                 unique_together in self.instance._meta.unique_together:                     if 'a_field_not_shown_on_form' not in unique_together:                         continue                     if err.lower() == '{} {} , {} exists.'.format(self.instance.__class__.__name__,                                                                                       unique_together[0],                                                                                       unique_together[1]).lower():                         e.message_dict['__all__'][idx] = '{} {} exists in {}'.format(self.instance.__class__.__name__,                                                                                                        unique_together[0].capitalize(),                                                                                                        self.instance.complex.name)          self._update_errors(e.message_dict) 

from django.utils.text import capfirst  class yourmodel(models.model):      # fields      def unique_error_message(self, model_class, unique_check):         opts = model_class._meta         model_name = capfirst(opts.verbose_name)          # unique field         field_name = self._meta.unique_together[0]         field_label = capfirst(opts.get_field(field_name).verbose_name)         # insert error error dict, sneaky         return _(u"%(model_name)s %(field_label)s exists.") %  {             'model_name': unicode(model_name),             'field_label': unicode(field_label)         }