Twisted (https://en.wikipedia.org/wiki/Twisted_(software)) has been around for longer than Node has existed. It is very effective at networking and async I/O use cases that are a sweet spot for Node, but the programming model differed from mainstream Python. It fell into a niche as many developers followed the WSGI-based approach for web development. With asyncio becoming available in Python it is re-integrating into the mainstream of the Python community (https://asyncio.readthedocs.io/en/latest/twisted.html).