History

An overview about AsyncIO related changes in Python.

Python 3.3

• A pluggable event loop, transport and protocol abstractions, and a higher-level scheduler based on yield from PEP 3156

Python 3.4

• asyncio library added to Python https://docs.python.org/3.10/whatsnew/3.4.html#new-modules. Before it was developed under the tulip umbrella.

Python 3.5

• Change StopIteration handling inside generators PEP 479

• async/await syntax PEP 492

Python 3.6

• Async Generators PEP 525

• Asynchronous Comprehensions PEP 530

Python 3.7

• asyncio.run

• asyncio.create_task

Python 3.8

• asyncio repl -> Running python -m asyncio launches a natively async REPL. This allows rapid experimentation with code that has a top-level await.

• unittest.mock.AsyncMock and unittest.IsolatedAsyncioTestCase

Python 3.9

• asyncio.to_thread -> for running IO-bound functions in a separate thread to avoid blocking the event loop

Python 3.10

• aiter and anext -> async versions of iter and next

Python 3.11

• TaskGroup -> structured concurrency in asyncio

• timeout and timeout_at -> implementation of trio’s cancel scope feature