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Python Code Samples

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

80 matches
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
Streaming & messaging medium

Kafka Consumer Poll Loop Mock in Python

Simulate a Kafka consumer poll loop with a mock class, process messages in batches, and commit offsets to understand streaming consumption patterns.

kafka streaming mock
Python
import time

class MockKafkaConsumer:
    def __init__(self, topic, messages):
        self.topic = topic
        self.messages = list(messages)
        self.position = 0

    def poll(self, timeout_ms=100):
        if self.position >= len(self.messages):
            time.sleep(timeout_ms / 1000)
            return []…
13 0 Open
Reliability & rate limiting medium

How to Mock a Liveness Check and Restart a Process in Python

Simulate a failing process and restart it after a liveness check fails, using a mock class and a liveness loop.

liveness restart mock
Python
import subprocess
import sys
import time
import os

class ProcessMock:
    def __init__(self, name, fail_after_seconds=3):
        self.name = name
        self.fail_after = fail_after_seconds
        self.start_time = None
        self.is_running = False

    def start(self):
        self.start_time = time.time()
   …
14 0 Open
Reliability & rate limiting medium

How to retry idempotent operations with a mock in Python

Wrap a flaky idempotent operation in a retry loop with exponential backoff, and use unittest.mock to deterministically test the str's behavior.

retry backoff mock
Python
import random
import time
from unittest.mock import Mock


def idempotent_operation(value):
    """Simulate an idempotent operation that sometimes fails."""
    if random.random() < 0.6:  # 60% failure rate
        raise ConnectionError("Temporary failure")
    return value * 2


def retry_with_backoff(operation, max_…
14 0 Open
ML engineering pipelines medium

Bayesian Optimization in Python: A Simplified Mock Implementation

A toy Bayesian optimization loop with a Gaussian process prior, expected improvement acquisition, and noisy sampling to find a function's minimum.

bayesian-optimization gaussian-process hyperparameter-tuning
Python
import random
import math

class BayesianOptimizer:
    def __init__(self, noise=0.1):
        self.noise = noise
        self.observations = []
    
    def objective(self, x):
        return (math.sin(3*x) + 0.5*x) / (1 + x**2)
    
    def gaussian_process_prior(self, x1, x2, length_scale=0.5):
        return math.…
13 0 Open
ML engineering pipelines medium

Mock a Flyte ML workflow in Python

Build a lightweight mock of a Flyte ML pipeline with dataclasses and a simple execution loop that passes outputs between tasks.

flyte ml-pipeline dataclass
Python
from dataclasses import dataclass, field
from typing import List, Dict, Optional
import time


@dataclass
class FlyteTask:
    name: str
    inputs: Dict = field(default_factory=dict)
    outputs: Dict = field(default_factory=dict)

    def run(self) -> Dict:
        time.sleep(0.1)  # simulate work
        return sel…
16 0 Open
Database scaling & optimization easy

How to Count Star vs Estimate Matches in Python

Count how many times 'star' and 'estimate' annotations match their actual labels in a list of mock comparison results.

counting dictionary matching
Python
def count_star_vs_estimate(mock_scores):
    """
    Count the number of times 'star' wins and 'estimate' wins
    from a list of mock comparison results.

    Args:
        mock_scores: list of tuples, each (annotation, actual)
                     where annotation is 'star' or 'estimate'

    Returns:
        dict w…
12 0 Open
Auth & security at scale medium

How to Tune scrypt Parameters in Python

Adjust scrypt work factor (N) to hit a target hashing time with a mock benchmark loop, then return tunable parameters and a derived key.

scrypt hashing password-security
Python
import hashlib

def tune_scrypt_params(target_time=0.1, base_n=2**14, base_r=8, base_p=1):
    """Mock tuning of scrypt params based on target time."""
    n, r, p = base_n, base_r, base_p
    iterations = 0
    
    for _ in range(5):  # simple mock adjustment loop
        iterations += 1
        mock_time = 0.05 + (…
14 0 Open

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  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.