<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def run_async(coro: Coroutine) -> None: """ Simple async runner that cleans up DB connections on exit. This is meant for simple scripts. Usage:: from tortoise import Tortoise, run_async async def do_stuff():
 await Tortoise.init( db_url='sqlite://db.sqlite3', models={'models': ['app.models']} ) run_async(do_stuff()) """

    loop = asyncio.get_event_loop()
    try:
        loop.run_until_complete(coro)
    finally:
        loop.run_until_complete(Tortoise.close_connections())