code: def app_templates_dirs(self):
          
          app_templates_dirs = OrderedDict()
          for app_config in apps.get_app_configs():
              templates_dir = os.path.join(
                  getattr(app_config, 'path', '/'), 'templates')
              if os.path.isdir(templates_dir):
                  templates_dir = upath(templates_dir)
                  app_templates_dirs[app_config.name] = templates_dir
                  app_templates_dirs[app_config.label] = templates_dir
          return app_templates_dirs
docs: Build a cached dict with settings.INSTALLED_APPS as keys
          and the 'templates' directory of each application as values.