code: def render_change_form(self, request, context, add=False, change=False, form_url='', obj=None):
          
          if self._has_translatable_model():
              lang_code = self.get_form_language(request, obj)
              lang = get_language_title(lang_code)
  
              available_languages = self.get_available_languages(obj)
              language_tabs = self.get_language_tabs(request, obj, available_languages)
              context['language_tabs'] = language_tabs
              if language_tabs:
                  context['title'] = '%s (%s)' % (context['title'], lang)
              if not language_tabs.current_is_translated:
                  add = True  # lets prepopulated_fields_js work.
  
              # Patch form_url to contain the "language" GET parameter.
              # Otherwise AdminModel.render_change_form will clean the URL
              # and remove the "language" when coming from a filtered object
              # list causing the wrong translation to be changed.
  
              params = request.GET.dict()
              params['language'] = lang_code
              form_url = add_preserved_filters({
                  'preserved_filters': urlencode(params),
                  'opts': self.model._meta
              }, form_url)
  
          # django-fluent-pages uses the same technique
          if 'default_change_form_template' not in context:
              context['default_change_form_template'] = self.default_change_form_template
  
          #context['base_template'] = self.get_change_form_base_template()
          return super(TranslatableAdmin, self).render_change_form(request, context, add, change, form_url, obj)
docs: Insert the language tabs.