def _init_detector_storage(self):
        if self.detector_storage is not None:
            self.context.modules.importer.import_item(
                config_key='detector_storage',
                item_value=self.context.config.MIXED_STORAGE_DETECTOR_STORAGE,
                class_name='Storage'
            )
            self.detector_storage = self.context.modules.detector_storage = \
                self.context.modules.importer.detector_storage(self.context)
dataset/ETHPy150Open thumbor/thumbor/thumbor/storages/mixed_storage.py/Storage._init_detector_storage/operator `is` -> `is not`