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:
run Python coroutines concurrently and have full control over their execution;
perform network IO and IPC;
distribute tasks via queues;
synchronize concurrent code;
Additionally, there are low-level APIs for library and framework developers to:
implement efficient protocols using transports;
bridge callback-based libraries and code with async/await syntax.
The source code for asyncio can be found in Lib/asyncio/.