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Python Code Samples

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

4 matches
Functions & basics easy

Benchmark list append vs comprehension in Python

This micro-benchmark compares the speed of building a list with a for loop and append versus a list comprehension, using the timeit module to get precise timings.

timeit benchmark performance
Python 
import timeit

# Build a list of the first 1,000,000 integers using append in a loop
def append_loop(n=1_000_000):
    result = []
    for i in range(n):
        result.append(i)
    return result

# Build the same list using a list comprehension
def comprehension(n=1_000_000):
    return [i for i in range(n)]

if __n…
13 0 Open
Functions & basics easy

How to Compare Two Implementations with timeit in Python

Measure and compare the execution time of iterative vs recursive factorial functions using the timeit module.

timeit benchmark performance
Python 
import timeit

def factorial_iterative(n):
    result = 1
    for i in range(2, n + 1):
        result *= i
    return result

def factorial_recursive(n):
    if n == 0:
        return 1
    return n * factorial_recursive(n - 1)

if __name__ == "__main__":
    n = 10
    iterations = 10000

    iterative_time = timeit…
13 0 Open
Concurrency & performance medium

Benchmark list.append vs deque.append in Python

Measures and compares the performance of appending to a Python list versus a collections.deque using timeit.repeat, showing best and average timings.

benchmark performance list
Python 
"""Benchmark list.append vs collections.deque.append."""

import timeit

def bench(stmt, setup, repeat=5, number=1_000_000):
    times = timeit.repeat(stmt, setup=setup, repeat=repeat, number=number)
    return min(times), sum(times) / len(times)

if __name__ == "__main__":
    number = 1_000_000
    list_best, list_a…
12 0 Open
Concurrency & performance easy

How to Time Code Performance with timeit in Python

Benchmark two implementations of the same logic using Python's timeit module and compare their execution speeds.

timeit performance benchmark
Python 
import timeit

# Implementation 1: Using a list comprehension
def list_comprehension_squares(n):
    return [i ** 2 for i in range(n)]

# Implementation 2: Using a for loop with append
def loop_squares(n):
    result = []
    for i in range(n):
        result.append(i ** 2)
    return result

if __name__ == "__main__"…
12 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.

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.