import websockets
import asyncio
import datetime
import random

async def handler(websocket, path):

    while True:
        now = datetime.datetime.utcnow().isoformat() + 'Z'
        await websocket.send(now)
        await asyncio.sleep(random.random() * 3)
    while True:
        message = await websocket.recv()
        await consumer(message)
        return message
    consumer_task = asyncio.ensure_future(consumer_handler(websocket))
    producer_task = asyncio.ensure_future(producer_handler(websocket))
    done, pending = await asyncio.wait(
        [consumer_task, producer_task],
        return_when=asyncio.FIRST_COMPLETED,

    )

    for task in pending:
        task.cancel()

print(message)


start_server = websockets.serve(handler, '127.0.0.1', 5678)

asyncio.get_event_loop().run_until_complete(start_server)
asyncio.get_event_loop().run_forever()
print(message)