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Python › File I/O & Context Managers

How would you implement asynchronous file I/O using aiofiles alongside an async context manager, to avoid blocking the event loop during file operations?

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Answer

Standard Python file I/O is BLOCKING (no native async file API in the standard library), so aiofiles wraps file operations in a thread pool internally while exposing an async context manager interface (`async with aiofiles.open(...) as f:`), letting file reads/writes coexist with other async work without blocking the event loop.
import aiofiles

async def read_file_async(path):
    async with aiofiles.open(path, mode="r") as f:
        content = await f.read()
    return content

async def main():
    content = await read_file_async("data.txt")
    print(content)
Real-world example Reading configuration or data files inside an async web server or scraper without blocking the event loop during disk I/O.

Common follow-ups: Why doesn't the Python standard library provide a NATIVE async file I/O API, unlike its native support for async networking?

Async Generators & Async Context Managers
All 15 File I/O & Context Managers questions