def _check_object_id_field(self):
        try:
            self.model._meta.get_field(self.fk_field)
        except FieldDoesNotExist:
            return [
                checks.Error(
                    self.fk_field % "The GenericForeignKey object ID references the non-existent field '%s'.",
                    obj=self,
                    id='contenttypes.E001',
                )
            ]
        else:
            return []
dataset/ETHPy150Open django/django/django/contrib/contenttypes/fields.py/GenericForeignKey._check_object_id_field/swapped operands of `%`