asyncio_example.py

'''
There are 2 types of functions normal `def func()` and `async def func()`:

- An asyc function can call async functions as well as normal ones
- A normal function can only call normal functions
'''

#%%
import asyncio
import datetime

async def main():
    print("start", datetime.datetime.now())
    await asyncio.sleep(3)
    print("end", datetime.datetime.now())
    return 5

async def more_main():
#%%
    print("This will run one after the other")

    coroutine = main()  # Create the coroutine instance, it will not run it
    await coroutine  # Run the instance and wait for it

    await main()  # Create and run it directly

#%%
    print("This will run in parallel")
    task1 = asyncio.create_task(main())  # This starts the task directly in the background
    task2 = asyncio.create_task(main())
    await task1  # Wait for the result
    await task2

#%%
    print("This will also run in parallel")
    await asyncio.gather(main(), main())  # The same, but for a list of coroutines

#%%
# This is necessary when running in a script to start the
# main async loop. You can have only one of these per thread.
coroutine = more_main()
asyncio.run(coroutine)