What are the differences between futures and asyncio in Python?

What are the differences between futures and asyncio in Python?

Futures are a way to represent a result that may not be available yet, while asyncio is a library for writing concurrent code using the async/await syntax. Futures can be used with asyncio, but asyncio provides a more structured approach to concurrency.

Can you give me an example of how to use futures?

Sure! You can use the concurrent.futures module to run tasks in a separate thread or process. Here's a simple example:

from concurrent.futures import ThreadPoolExecutor

def task(n):
    return n * n

with ThreadPoolExecutor() as executor:
    futures = [executor.submit(task, i) for i in range(5)]
    results = [future.result() for future in futures]
print(results)  # Output: [0, 1, 4, 9, 16]

How does asyncio handle tasks differently?

Asyncio uses an event loop to manage tasks. You define coroutines with async def and use await to yield control back to the event loop, allowing other tasks to run. Here's a quick example:

import asyncio

async def task(n):
    await asyncio.sleep(1)
    return n * n

async def main():
    results = await asyncio.gather(*(task(i) for i in range(5)))
    print(results)

asyncio.run(main())  # Output: [0, 1, 4, 9, 16]