RuntimeError: No Running Event Loop

Why This Happens

asyncio functions like asyncio.create_task() require a running event loop. If called from synchronous code without an active loop, this error is raised.

The Problem

import asyncio
async def fetch():
    return 'data'
task = asyncio.create_task(fetch())

The Fix

import asyncio
async def fetch():
    return 'data'

async def main():
    task = asyncio.create_task(fetch())
    result = await task
    return result

result = asyncio.run(main())

Step-by-Step Fix

1. 1

   Use asyncio.run()

   Wrap your async entry point in asyncio.run(main()).

2. 2

   Create tasks inside async functions

   Only use asyncio.create_task() from within async functions.

3. 3

   Avoid deprecated APIs

   In Python 3.10+, use asyncio.run() instead of get_event_loop().