asyncio — Asynchronous I/O

asyncio is a library to write concurrent code using the async/await syntax.

asyncio is used as a foundation for multiple Python asynchronous frameworks that provide high-performance network and web-servers, database connection libraries, distributed task queues, etc.

asyncio is often a perfect fit for IO-bound and high-level structured network code.

asyncio provides a set of high-level APIs to:

Additionally, there are low-level APIs for library and framework developers to:


High-level APIs

Low-level APIs

Guides and Tutorials


The source code for asyncio can be found in Lib/asyncio/.


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