example2.py

# ch10/example2.py

import asyncio
import time

async def count_down(name, delay):
    indents = (ord(name) - ord('A')) * '\t'

    n = 3
    while n:
        await asyncio.sleep(delay)

        duration = time.perf_counter() - start
        print('-' * 40)
        print('%.4f \t%s%s = %i' % (duration, indents, name, n))

        n -= 1

loop = asyncio.get_event_loop()
tasks = [
    loop.create_task(count_down('A', 1)),
    loop.create_task(count_down('B', 0.8)),
    loop.create_task(count_down('C', 0.5))
]

start = time.perf_counter()
loop.run_until_complete(asyncio.wait(tasks))

print('-' * 40)
print('Done.')