Async error: event loop already running

Not sure this is an IPython issue because it happens only in a Jupyter Notebook, but the following code gives a RuntimeError: This event loop is already running (IPython 7.0.1, Python 3.7.0, notebook server 5.7.0). No problem with IPython 7.0.1, Python 3.6.3, notebook server 5.3.1.

import asyncio

async def foo():
    await asyncio.sleep(1)
    print('done')

loop = asyncio.get_event_loop()

loop.run_until_complete(foo())

[davidbrochart]

Having this a the beginning of your notebook should fix this issue:

import nest_asyncio
nest_asyncio.apply()

[Carreau]

Yes, is is documented in the what’s new and auto-async documentation with pointer to workarounds.

Thanks for testing IPython 7.0 !