Reference library

Python Code Samples

Medium snippets you can copy, study, and run in the browser editor.

3 matches
Caching & Redis medium

How to Implement a Write-Through Cache in Python with a Mock Database

A thread-safe write-through cache that updates both cache and mock database atomically, computing values only after a successful write to the database.

caching write-through threading
Python
import threading
import time
import random


class WriteThroughCache:
    def __init__(self):
        self.cache = {}
        self.db = {}
        self.lock = threading.Lock()

    def write(self, key, value):
        with self.lock:
            # Simulate slow database write
            time.sleep(random.uniform(0.01…
12 0 Open
Big data & Spark medium

How to Create a Mock Iceberg Snapshot Manifest in Python

Build a mock Iceberg snapshot manifest structure with metadata and data entries using Python dictionaries and JSON.

iceberg manifest snapshot
Python
import json
from datetime import datetime, timezone


def create_mock_manifest(snapshot_id: int, file_paths: list[str]) -> dict:
    """Create a mock Iceberg snapshot manifest structure."""
    manifest_file = {
        "manifest_path": f"/warehouse/table/metadata/snap-{snapshot_id}-m0.avro",
        "manifest_length"…
15 0 Open
Database scaling & optimization medium

Simulate Shard Key Cardinality in Python

Generate mock data with configurable cardinality to evaluate shard key distribution and detect hotspots in database scaling design.

sharding cardinality database
Python
import random
import string

def calculate_cardinality(values):
    """Return the number of distinct values in the given list."""
    return len(set(values))

def generate_mock_data(num_records, cardinality):
    """Generate mock records for a shard key with given cardinality."""
    possible_keys = [f"key_{i:04d}" fo…
17 0 Open

Browse by section

Each section groups closely related Python snippets.

Guide: free Python code samples library

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.