code: def _get_user_allowed_fields(self):
          
          model_name = self.Meta.model.__name__.lower()
          app_label = self.Meta.model._meta.app_label
          full_model_name = '%s.%s' % (app_label, model_name)
          permissions = self.cached_allowed_fields.get(full_model_name)
  
          if not permissions:
              permissions = FieldPermission.objects.filter(
                  user_field_permissions__user=self.user,
                  content_type__model=model_name,
                  content_type__app_label=app_label
              )
              self.cached_allowed_fields[full_model_name] = permissions
          return permissions
docs: Retrieve all allowed field names ofr authenticated user.