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Python Code Samples

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

2 matches
Algorithms & data structures easy

Extract n largest elements from a large list using heapq

Uses heapq.nlargest to efficiently extract the top n largest numbers from a large list, even with millions of elements.

heapq heaps large-data
Python
import heapq
import random

def n_largest(numbers, n):
    """Return the n largest numbers from a list using heapq."""
    if n <= 0:
        return []
    return heapq.nlargest(n, numbers)

if __name__ == "__main__":
    # Create a large list with 1,000,000 random numbers
    large_list = [random.randint(1, 1_000_000…
14 0 Open
Database scaling & optimization easy

How to Limit a Result Set to Top N Rows in Python

Sort a list of dictionaries by a numeric key and return only the top N results, formatted as a readable ranked list.

sorting slicing top-n
Python
import random

def top_n_mock(limit: int = 5):
    """Return a formatted top-N result set as a mock example."""
    # Simulated data source
    scores = [
        {"name": "Alice", "score": 87},
        {"name": "Bob", "score": 92},
        {"name": "Charlie", "score": 78},
        {"name": "Diana", "score": 95},
    …
16 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.