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Python Code Samples

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

5 matches
Functions & basics easy

How to Create a Timing Decorator in Python

A Python decorator that measures and prints the execution time of any function using time.perf_counter.

decorator timing perf_counter
Python
import time
from functools import wraps


def timing_decorator(func):
    @wraps(func)
    def wrapper(*args, **kwargs):
        start = time.perf_counter()
        result = func(*args, **kwargs)
        end = time.perf_counter()
        elapsed = end - start
        print(f"{func.__name__} took {elapsed:.6f} seconds"…
11 0 Open
Functions & basics easy

Profile Python functions with cProfile

Profile a Python program with cProfile, capture the stats in memory, and print a sorted performance report.

cprofile performance profiling
Python
import cProfile
import pstats
import io


def slow_function():
    total = 0
    for i in range(100000):
        total += i ** 2
    return total


def medium_function():
    return sum(range(10000))


def fast_function():
    return sum(range(100))


def main():
    result1 = slow_function()
    result2 = medium_func…
11 0 Open
Concurrency & performance medium

Build a Python Performance Profiler That Generates Readable Reports

Use cProfile and pstats to profile Python functions and print a sorted performance report showing the top time-consuming calls.

profiling cprofile pstats
Python
import cProfile
import pstats
import io
from pathlib import Path

def slow_function():
    total = 0
    for i in range(500_000):
        total += i ** 2
    return total

def fast_function():
    total = sum(i * i for i in range(500_000))
    return total

def profile_functions():
    profiler = cProfile.Profile()
  …
44 0 Open
Concurrency & performance medium

How to Profile CPU Hot Path in Python with cProfile and sort_stats cumtime

Profile a Python function's CPU usage by running cProfile, sorting stats by cumulative time, and printing a readable report to stdout.

cprofile profiling performance
Python
import cProfile
import pstats
import io


def slow_function():
    total = 0
    for i in range(100_000):
        total += i * i
    return total


def fast_function():
    return sum(i for i in range(100))


def main():
    slow_function()
    fast_function()


if __name__ == "__main__":
    profiler = cProfile.Profi…
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.