Reference library

Python Code Samples

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

4 matches
Automation & scripting medium

Create a Local Search Engine to Instantly Find Files on Your Computer in Python

Build a local file search engine in Python that indexes files by name, extension, and glob pattern for instant retrieval.

file search indexing os.walk
Python 
import os
import sys
import time
from pathlib import Path
import fnmatch

class LocalSearchEngine:
    def __init__(self, root_directory="."):
        self.root_directory = Path(root_directory)
        self.file_index = {}
        
    def build_index(self):
        """Build a complete index of files in the root direc…
42 0 Open
Database scaling & optimization medium

Composite index leftmost prefix in Python

Simulate a composite index in SQLite and check whether query columns match the leftmost prefix rule for index usage.

sqlite indexes database
Python 
import sqlite3


def get_indexed_columns(table_name):
    """Simulate a composite index by reading column names that start with 'idx_'."""
    conn = sqlite3.connect(":memory:")
    conn.execute(f"CREATE TABLE {table_name} (id INTEGER, idx_col1 TEXT, idx_col2 INTEGER, other TEXT)")
    conn.execute(f"CREATE INDEX idx_…
13 0 Open
Database scaling & optimization easy

Database indexing and query timing optimization in Python

Create SQLite indexes and time query performance to measure speedup for large table lookups in Python.

sqlite indexing query optimization
Python 
import sqlite3
import time


def time_query(db_path, query, params=()):
    conn = sqlite3.connect(db_path)
    conn.execute("PRAGMA journal_mode = WAL")
    start = time.perf_counter()
    result = conn.execute(query, params).fetchall()
    elapsed = time.perf_counter() - start
    conn.close()
    return result, ela…
14 0 Open
Database scaling & optimization easy

How to Shard Data by User ID Hash in Python

Deterministically map user IDs to shard indexes using an MD5 hash modulo the shard count in Python.

sharding hashing md5
Python 
import hashlib

def shard_id(user_id: str, num_shards: int = 4) -> int:
    """Deterministically map a user_id to a shard index using MD5."""
    digest = hashlib.md5(user_id.encode("utf-8")).hexdigest()
    return int(digest[:8], 16) % num_shards

if __name__ == "__main__":
    user_ids = ["alice", "bob", "carol", "d…
11 0 Open

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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.

Related coding tools

Free online Python IDE Write and run Python in your browser — no install. Free Python code formatter Format with autopep8 — side-by-side PEP 8 cleanup.