All 15 Async Generators & Async Context Managers questions
More in Async Generators & Async Context Managers
What is an async generator, and how does it differ from a regular generator? How do you consume an async generator using 'async for'? How do you write an async context manager more concisely using @contextlib.asynccontextmanager? How does an async generator interact with try/finally for guaranteed cleanup, similar to regular generators? How do you build an async generator pipeline, chaining one async generator's output into another, like a synchronous generator pipeline? How do async comprehensions work, combining 'async for' directly inside a list/set/dict comprehension? How would you implement a custom async iterator class from scratch, without using an async generator function? How do you handle backpressure when an async generator produces items faster than the consumer can process them? How would you implement timeout handling for an async generator's individual yields, so a stalled source doesn't hang the consumer forever? How do async generators interact with asyncio.Queue to implement a producer-consumer pattern across separate tasks?
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Python › Async Generators & Async Context Managers

What is an async context manager, and which two dunder methods does it require?

Beginner

Answer

An async context manager implements __aenter__ and __aexit__ (both coroutines, defined with 'async def') instead of the synchronous __enter__/__exit__ — used with 'async with' to manage a resource whose setup or teardown itself requires awaiting, like an async database connection.
class AsyncConnection:
    async def __aenter__(self):
        await self.connect()
        return self
    async def __aexit__(self, exc_type, exc, tb):
        await self.disconnect()

async def main():
    async with AsyncConnection() as conn:
        await conn.query("SELECT 1")
Real-world example Managing an async database or HTTP client session where opening/closing the connection are themselves async operations.

Common follow-ups: What happens to __aexit__ if an exception is raised inside the 'async with' block?

Concurrency (asyncio/threading/multiprocessing)
All 15 Async Generators & Async Context Managers questions