requires python >= 3.4

asyncio_accept.py

import asyncio


def on_accept(r, w):
    print("new client accepted.")
    print(r, w)

if __name__ == "__main__":
    future = asyncio.start_server(on_accept, host="127.0.0.1", port=5555)
    asyncio.async(future)
    asyncio.get_event_loop().run_forever()