Python Code
Samples
Copy-ready Python snippets by topic and difficulty — short, focused, and runnable in the browser editor.
Batch Rename Hundreds of Files in Python
Rename all files with a given extension inside a folder using a sequential counter and a custom prefix.
import os
from pathlib import Path
def batch_rename_files(directory: str, prefix: str, extension: str = ".txt") -> None:
"""Rename all files with given extension in directory to prefix_{counter}.ext."""
path = Path(directory)
if not path.is_dir():
print(f"Directory '{directory}' does not exist.")
…
Benchmark File Read and Write Speed in Python
Measures file write and read throughput in MB/s by writing and reading a temporary file of a given size.
import os
import time
import tempfile
def benchmark_write(file_path, size_mb=100):
data = b'x' * (1024 * 1024) # 1 MB block
start = time.perf_counter()
with open(file_path, 'wb') as f:
for _ in range(size_mb):
f.write(data)
elapsed = time.perf_counter() - start
return size_mb …
Build a Command-Line Password Generator in Python
Generate cryptographically strong random passwords using Python's secrets module and print them for command-line use.
import secrets
import string
def generate_password(length=16):
"""Generate a cryptographically strong random password."""
alphabet = string.ascii_letters + string.digits + string.punctuation
password = ''.join(secrets.choice(alphabet) for _ in range(length))
return password
if __name__ == "__main__":…
Build a Complete Web Scraper with Requests and BeautifulSoup in Python
Scrape multiple paginated pages from a website using Requests and BeautifulSoup, with retry logic, error handling, and CSV export.
import requests
from bs4 import BeautifulSoup
import csv
import time
from typing import List, Dict, Optional
class WebScraper:
def __init__(self, base_url: str, output_file: str = "scraped_data.csv"):
self.base_url = base_url
self.output_file = output_file
self.session = requests.Session()…
Build a Complete Website Sitemap Generator Without External Services
Crawl a website recursively using only Python's standard library to generate a structured sitemap of internal links.
import json
from urllib.parse import urlparse, urljoin
from collections import deque
import urllib.request
import urllib.error
import re
from html.parser import HTMLParser
class SitemapParser(HTMLParser):
def __init__(self, base_url):
super().__init__()
self.base_url = base_url
self.links …
Build a Live Countdown Timer for Events in Python
A Python script that displays a real-time countdown to a target date and time, updating every second in the console.
import datetime
import time
def countdown(event_name, target_datetime):
"""Displays a live countdown to a target datetime."""
while True:
now = datetime.datetime.now()
remaining = target_datetime - now
if remaining.total_seconds() <= 0:
print(f"\n🚀 {event_name} is happening…
Build a Network Ping Monitor in Python
A Python script that continuously pings a remote host using subprocess and reports connectivity status with timestamps and latency.
import subprocess
import time
def ping_host(host, count=4):
"""Ping a host and return the results."""
try:
# Platform-independent ping command
cmd = ["ping", "-c", str(count), host]
result = subprocess.run(cmd, capture_output=True, text=True, timeout=10)
return result.stdout, r…
Build a Python Tool to Find All API Endpoints on a Website
A Python script that crawls a website, searches for common API endpoint patterns in HTML and JavaScript, and returns all discovered public API URLs.
import re
import requests
from urllib.parse import urljoin, urlparse
from collections import deque
def find_api_endpoints(base_url, max_pages=10):
visited = set()
queue = deque([base_url])
api_endpoints = set()
api_patterns = [
r'/api/[a-zA-Z0-9_/-]+',
r'/v[0-9]+/[a-zA-Z0-9_/-]+',…
Build a Terminal Dashboard That Displays Real-Time System Performance in Python
A Python script that reads Linux system files to display a real-time terminal dashboard with CPU usage, memory usage, and CPU temperature.
import os, time, sys
from collections import deque
def get_cpu_temp():
try:
with open("/sys/class/thermal/thermal_zone0/temp") as f:
return round(int(f.read().strip()) / 1000, 1)
except:
return None
def get_mem_usage():
with open("/proc/meminfo") as f:
lines = f.readli…
Bulk Rename Files in Python with Regex Replacement
Renames every file in a directory by applying a regex substitution to its filename using Python's stdlib re and pathlib.
import re
from pathlib import Path
def bulk_rename_regex(directory, pattern, replacement):
path = Path(directory)
renamed = []
for file in path.iterdir():
if file.is_file():
new_name = re.sub(pattern, replacement, file.name)
if new_name != file.name:
new_pat…
Check Service Ping Status and Exit Code in Python
Ping a list of hosts, print OK/FAIL per host, and exit with a non-zero code when any host is unreachable.
import subprocess
import sys
SERVICES = [
"8.8.8.8",
"1.1.1.1",
"invalid-host",
]
def main():
failed = []
for host in SERVICES:
result = subprocess.run(
["ping", "-c", "1", "-W", "2", host],
stdout=subprocess.DEVNULL,
stderr=subprocess.DEVNULL,
…
Convert DOCX to Text by Unzipping XML in Python
Extract plain text from a .docx file by unzipping the container and parsing word/document.xml with regex, using only Python's standard library.
import zipfile
import re
from pathlib import Path
def docx_to_text_unzip_xml(docx_path: str) -> str:
"""Extract plain text from a .docx file by unzipping and parsing document.xml."""
docx_path = Path(docx_path)
if not docx_path.exists():
raise FileNotFoundError(f"File not found: {docx_path}")
…
Convert HTML Tables to Excel Reports in Python
Convert HTML tables into formatted Excel reports using BeautifulSoup and Pandas with auto-adjusted column widths.
import pandas as pd
from bs4 import BeautifulSoup
from pathlib import Path
def html_table_to_excel(html_file: str, excel_file: str) -> None:
"""Convert HTML table to formatted Excel report."""
with open(html_file, 'r', encoding='utf-8') as f:
html_content = f.read()
soup = BeautifulSoup(html_…
Convert Markdown to HTML in Python (Batch)
Convert every Markdown file in a directory to HTML with the Python markdown library, saving each result with an .html extension.
import markdown
from pathlib import Path
def convert_md_to_html(source_dir: str, dest_dir: str) -> list[str]:
src = Path(source_dir)
dst = Path(dest_dir)
dst.mkdir(parents=True, exist_ok=True)
converted_files = []
for md_file in src.glob("*.md"):
html_content = markdown.markdown(md_file.…
Create ICS Calendar Invites in Python
This script generates a batch of calendar invites in the ICS format using the ics library.
import ics
from datetime import datetime, timedelta
def create_invites(batch):
calendar = ics.Calendar()
for event_data in batch:
event = ics.Event()
event.name = event_data["name"]
event.begin = event_data["start"]
event.end = event_data["end"]
event.description = even…
Create Mock Watermarked Image Bytes in Python Without PIL
Builds a mock image-like byte stream with an embedded watermark using only stdlib modules, for testing pipelines without PIL.
from io import BytesIO
import zlib
import struct
def create_watermarked_bytes(width: int, height: int, watermark: bytes) -> bytes:
"""Create a mock image-like byte stream with a watermark (no PIL)."""
header = struct.pack("<2I", width, height)
payload = watermark * max(1, (width * height // max(1, len(wa…
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.
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…
Create a Python Script That Detects Website Technology Stack Automatically
This script sends an HTTP request to a URL and inspects headers and HTML content to identify technologies like servers, frameworks, and JavaScript libraries.
import requests
from re import search
def detect_tech_stack(url):
tech_stack = []
try:
response = requests.get(url, timeout=5, headers={'User-Agent': 'Mozilla/5.0'})
headers = response.headers
html = response.text.lower() if response.text else ''
# Check server header
…
Create a Simple HTTP File Server in Python
This code creates a simple HTTP file server that serves files from the current working directory on port 8000 using Python's built-in http.server module.
import http.server
import socketserver
import os
PORT = 8000
DIRECTORY = os.getcwd()
class CustomHandler(http.server.SimpleHTTPRequestHandler):
def __init__(self, *args, **kwargs):
super().__init__(*args, directory=DIRECTORY, **kwargs)
def log_message(self, format, *args):
print(f"[{self.log…
Detect Circular Imports Across Python Projects Automatically
This script walks through all .py files in a directory, builds an import graph, and uses depth-first search to find cycles—printing each circular dependency chain.
import ast
import sys
from pathlib import Path
from collections import defaultdict, deque
def find_imports(filepath):
"""Return set of module names imported by a Python file."""
imports = set()
try:
with open(filepath) as f:
tree = ast.parse(f.read())
except (SyntaxError, UnicodeDe…
Detect Memory Leaks in Python with Weak References
A custom LeakDetector uses weak references and garbage collection to find class instances that survive past expected cleanup in long-running Python applications.
import gc
import sys
import weakref
import time
from collections import defaultdict
class LeakDetector:
def __init__(self):
self._tracked = defaultdict(list)
def track_class(self, cls):
"""Track all instances of a class for leak detection."""
old_init = cls.__init__
def new_in…
Detect and Remove Blurry Images in Python with OpenCV
Automatically scan a directory of images, detect blur using Laplacian variance, and remove blurry images with a dry-run option for safety.
from pathlib import Path
import cv2
import numpy as np
def is_blurry(image_path, threshold=100.0):
"""
Detect if an image is blurry using Laplacian variance.
Returns True if blurry, False otherwise.
"""
img = cv2.imread(str(image_path), cv2.IMREAD_GRAYSCALE)
if img is None:
return True…
Discover RSS Feeds From Any Website in Python
Scrape a website's HTML to automatically find all linked RSS or Atom feed URLs using requests, BeautifulSoup, and regex.
import requests
import re
from urllib.parse import urljoin, urlparse
from bs4 import BeautifulSoup
def discover_rss_feeds(url):
"""Discover all RSS/Atom feeds linked from a given website."""
try:
headers = {'User-Agent': 'Mozilla/5.0 (compatible; RSSDiscovery/1.0)'}
response = requests.get(url…
Download Images from a Web Page Automatically in Python
Scrape all images from a webpage, filter by extension, and save them to a local folder using requests and BeautifulSoup.
import requests
from bs4 import BeautifulSoup
from urllib.parse import urljoin
import os
def download_images(url, output_folder="downloaded_images"):
"""Download all images from a given URL."""
os.makedirs(output_folder, exist_ok=True)
response = requests.get(url)
response.raise_for_status()
…
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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.
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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.