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Python Code Samples

Copy-ready Python snippets by topic and difficulty — short, focused, and runnable in the browser editor.

4 matches
Concurrency & performance medium

How to Run Blocking Code in an Executor with asyncio in Python

This code runs blocking functions concurrently without stalling the event loop by offloading them to thread pool executors via asyncio.

asyncio executor concurrency
Python 
import asyncio
import time


def blocking_task(name: str, duration: float) -> str:
    """Simulate a blocking operation."""
    time.sleep(duration)
    return f"Finished {name} after {duration}s"


async def main() -> None:
    loop = asyncio.get_running_loop()
    results = await asyncio.gather(
        loop.run_in_…
13 0 Open
Concurrency & performance easy

How to Use uvloop Faster Event Loop

Install uvloop at startup to replace asyncio's default event loop with a faster libuv-based one, with a graceful fallback when it's unavailable.

uvloop asyncio event-loop
Python 
import asyncio
try:
    import uvloop
    uvloop.install()
    USING_UVLOOP = True
except ImportError:
    USING_UVLOOP = False


async def fetch_data(index):
    await asyncio.sleep(0.01)
    return f"data-{index}"


async def main():
    tasks = [fetch_data(i) for i in range(10)]
    results = await asyncio.gather(*…
14 0 Open
Concurrency & performance easy

How to set a timeout with asyncio.wait_for in Python

Use asyncio.wait_for to bound an async function with a timeout, catching TimeoutError when it exceeds the limit.

asyncio timeout concurrency
Python 
import asyncio

async def slow_task():
    await asyncio.sleep(3)
    return "finished"

async def main():
    try:
        result = await asyncio.wait_for(slow_task(), timeout=1)
        print(result)
    except asyncio.TimeoutError:
        print("Task timed out")

if __name__ == "__main__":
    asyncio.run(main())
13 0 Open
Concurrency & performance easy

asyncio sleep cooperative scheduling demo in Python

This demo shows how asyncio.sleep yields control between concurrent tasks, letting multiple workers interleave their ticks.

asyncio concurrency scheduling
Python 
import asyncio

async def worker(name, delay):
    for i in range(3):
        print(f"{name}: tick {i}")
        await asyncio.sleep(delay)
    return f"{name} done"

async def main():
    tasks = [
        asyncio.create_task(worker("A", 0.1)),
        asyncio.create_task(worker("B", 0.2)),
        asyncio.create_tas…
12 0 Open

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Copy-ready Python snippets for learners and developers

PythonSkillset code samples are short, focused examples organised by topic and difficulty. Every snippet is server-rendered HTML — readable by search engines and easy to copy. Open any sample, read the notes, copy the code, then press Try in editor to run it in the browser with Pyodide.

How to use this library

  1. Pick a topic section — strings, lists, files, functions, and more
  2. Open a sample, read How it works, and copy the code block
  3. Run it in the IDE, tweak values, then take a related quiz or tutorial lesson

Samples vs tutorials and challenges

Samples are quick reference — one concept per page. For step-by-step teaching, use our Python tutorials. To test yourself, try quizzes or coding challenges. Clean up style with the Python formatter.

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