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How to Propagate Context Variables with asyncio in Python

Use Python's ContextVar with asyncio to carry deadline information across concurrent tasks and propagate context automatically.

contextvars asyncio concurrency

Python

import asyncio
from contextvars import ContextVar
from datetime import datetime

deadline = ContextVar("deadline", default=None)

async def worker(name):
    current = deadline.get()
    if current:
        print(f"{name} sees deadline: {current}")
    else:
        print(f"{name} sees no deadline")
    await asyncio.…

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