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Python Code Samples

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

3 matches
Functions & basics easy

Python Function Default Parameters Explained with Examples

Learn how to define Python functions with default parameter values and call them with fewer arguments than declared.

functions default-parameters args
Python
def greet(name, greeting="Hello", punctuation="!"):
    return f"{greeting}, {name}{punctuation}"

def calculate_area(length, width=1, unit="sq units"):
    area = length * width
    return f"Area: {area} {unit}"

if __name__ == "__main__":
    print(greet("Alice"))
    print(greet("Bob", "Hi"))
    print(greet("Charl…
14 0 Open
AI & LLM integration patterns easy

Chain of Thought Prompting in Python: Step-by-Step Reasoning Demo

This demo shows how to structure a function that explains its own reasoning step-by-step, mimicking chain-of-thought prompting for AI systems.

ai llm reasoning
Python
def solve_math_step_by_step(expression: str) -> str:
    """Solves a simple expression, showing each reasoning step."""
    # Step 1: Parse the expression (assume "a + b" or "a - b")
    parts = expression.split()
    a = int(parts[0])
    op = parts[1]
    b = int(parts[2])
    
    steps = []
    steps.append(f"Step…
16 0 Open
Database scaling & optimization medium

How to Explain SQLite Query Plans in Python

Build a Python function that runs EXPLAIN QUERY PLAN on SQLite in-memory tables and prints the optimizer's execution plan for any SELECT statement.

sqlite query-plan optimization
Python
import sqlite3

def explain_query(sql: str) -> str:
    """Return the SQLite query plan for the given SQL statement."""
    conn = sqlite3.connect(":memory:")
    cursor = conn.cursor()
    
    # Create sample data for a realistic plan
    cursor.execute("CREATE TABLE users (id INTEGER PRIMARY KEY, name TEXT)")
    c…
14 0 Open

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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.