“asyncio.run() cannot be called from a running event loop” when using Jupyter Notebook

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The asyncio.run() documentation says:

This function cannot be called when another asyncio event loop is running in the same thread.

In your case, jupyter (IPython ≥ 7.0) is already running an event loop:

You can now use async/await at the top level in the IPython terminal and in the notebook, it should — in most of the cases — “just work”. Update IPython to version 7+, IPykernel to version 5+, and you’re off to the races.

Therefore you don’t need to start the event loop yourself and can instead call await main(url) directly, even if your code lies outside any asynchronous function.

Jupyter (IPython ≥ 7.0)

async def main():
    print(1)
    
await main()

Python ≥ 3.7 and IPython < 7.0

import asyncio

async def main():
    print(1)
    
asyncio.run(main())

In your code that would give:

url = ['url1', 'url2']
result = await main(url)

for text in result:
    pass # text contains your html (text) response

Caution

There is a slight difference on how Jupyter uses the loop compared to IPython.

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