code: def clean(self):
          
  
          # First make sure the super's clean method is called upon.
          super(TranslationFormSet, self).clean()
  
          if settings.HIDE_LANGUAGE:
              return
  
          if len(self.forms) > 0:
              # If a default language has been provided, make sure a translation
              # is available
  
              if settings.DEFAULT_LANGUAGE and not any(self.errors):
                  # Don't bother validating the formset unless each form is
                  # valid on its own. Reference:
                  # http://docs.djangoproject.com/en/dev/topics/forms/formsets/#custom-formset-validation
  
                  for form in self.forms:
                      language_code = form.cleaned_data.get(
                          'language_code', None
                      )
  
                      if language_code == settings.DEFAULT_LANGUAGE:
  
                          # All is good, don't bother checking any further
                          return
  
                  raise forms.ValidationError(_(
                      'No translation provided for default language \'%s\'.'
                  ) % settings.DEFAULT_LANGUAGE)
  
          else:
              raise forms.ValidationError(
                  _('At least one translation should be provided.')
              )
docs: Make sure there is at least a translation has been filled in. If a
          default language has been specified, make sure that it exists amongst
          translations.