"Asyncio Event Loop is Closed" when getting loop

user_6520128 0
Viewed 91853

When trying to run the asyncio hello world code example given in the docs:

import asyncio

async def hello_world():
    print("Hello World!")

loop = asyncio.get_event_loop()
# Blocking call which returns when the hello_world() coroutine is done
loop.run_until_complete(hello_world())
loop.close()

I get the error: 

RuntimeError: Event loop is closed

I am using python 3.5.3.

python-3.5 python-asyncio python
3 Answers

On Windows seems to be a problem with EventLoopPolicy, use this snippet to work around it:

asyncio.set_event_loop_policy(asyncio.WindowsSelectorEventLoopPolicy())
asyncio.run(main())
user_63878800

...and just in case:

import platform
if platform.system()=='Windows':
    asyncio.set_event_loop_policy(asyncio.WindowsSelectorEventLoopPolicy())

If you ever deploy your code in the cloud it might avoid painful debug.

user_179663380
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