Print async

This is almost the same example as the previous one using sync, but we wait asynchronously.
The order of the output is now different.
It also finishes 1 sec faster. It finishes when the longest wait ends.

What did we don?

We added async in-front of the function definitions to make them co-routines.
We replaced the time.sleep by asyncio.sleep that can handle async sleep.
We called this new sleep function with the await keyword. That tells the even-loop that other tasks can run till this thing we are awaiting-for finishes.
We called the say function inside an await-ed call to asyncio.gather.
We started the event loop with asyncio.run.

Code

import time
import asyncio

async def say(text, sec):
    await asyncio.sleep(sec)
    print(text)

async def main():
    print('start main')
    start = time.monotonic()
    await asyncio.gather(
        say("First", 2),
        say("Second", 1),
    )
    end = time.monotonic()
    print(f"Elapsed: {end-start}")

main_co = main()
print(main_co)
asyncio.run(main_co)

Output

<coroutine object main at 0x78265ad9a4d0>
start main
Second
First
Elapsed: 2.0022734529920854

The first print shows that what the main function returns is a object of type coroutine.

The "Second" print appears before the "First", because the former only had to wait 1 second why the latter waited 2 seconds.

asyncio
async
await
gather