<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def _persist_result(self):
 """Store this Async's result in persistent storage."""

        self._prepare_persistence_engine()

        return self._persistence_engine.store_async_result(
            self.id, self.result)