Automation & scripting
CLI tools, scheduled jobs, filesystem tasks, and glue scripts that save time.
How to Filter Docker Containers for Pruning in Python
Simulate Docker's container prune by filtering a JSON list for exited containers older than a cutoff, returning pruned IDs and space freed.
import json
from datetime import datetime, timedelta
def parse_docker_ps(json_output: str, older_than_hours: int = 24) -> list:
containers = json.loads(json_output)
cutoff = datetime.now() - timedelta(hours=older_than_hours)
return [
c for c in containers
if datetime.fromisoformat(c["crea…
How to Find Stale GitHub Issues in Python
Filter a list of GitHub issues to find those not updated within a configurable number of days using Python datetime arithmetic.
import os
from datetime import datetime, timezone, timedelta
import re
# Simulated GitHub issue data structure
SAMPLE_ISSUES = [
{"number": 101, "title": "Login button not working", "updated_at": "2025-06-01T12:00:00Z", "assignee": "alice"},
{"number": 102, "title": "Fix database migration error", "updated_at…
How to Generate Thumbnails While Maintaining Aspect Ratio in Python
Resize images to fit within maximum dimensions while preserving the original aspect ratio using Pillow (PIL).
from PIL import Image
def thumbnail_with_aspect_ratio(image_path, output_path, max_width, max_height):
with Image.open(image_path) as img:
# Get original dimensions
width, height = img.size
# Calculate scaling ratio to fit within max dimensions
ratio = min(max_width / width, max_h…
How to Generate a QR Code in Python
Generate a QR code image from a URL string using the qrcode library and save it as a PNG file.
import qrcode
# Data to encode
data = "https://www.example.com"
# Create QR code instance
qr = qrcode.QRCode(
version=1,
error_correction=qrcode.constants.ERROR_CORRECT_L,
box_size=10,
border=4,
)
# Add data to QR code
qr.add_data(data)
qr.make(fit=True)
# Create an image from the QR code
img = qr.…
How to Generate a cloud-init User Data Mock in Python
Generate a cloud-init user data mock for a VM using a dataclass and JSON in Python.
import json
from dataclasses import dataclass, asdict
@dataclass
class VMConfig:
hostname: str
cpus: int
memory_mb: int
ssh_key: str
def generate_cloud_init_mock(config: VMConfig) -> str:
"""Build a cloud-init user-data mock for a VM."""
user_data = {
"hostname": config.hostname,
…
How to Generate an Inventory CSV of Installed pip Packages in Python
This script uses subprocess and csv to list all installed pip packages and write their names and versions into a CSV inventory file.
import subprocess
import csv
def get_installed_packages():
"""Return a list of (name, version) tuples for installed pip packages."""
result = subprocess.run(
["pip", "list", "--format=freeze"],
capture_output=True,
text=True,
check=True
)
packages = []
for line in r…
How to Hash Duplicate Photos and Delete Copies in Python
This script hashes image files in a directory using SHA-256 and deletes duplicate copies while keeping the first occurrence, ideal for cleaning up photo libraries.
from pathlib import Path
import hashlib
def file_hash(path, chunk_size=8192):
hasher = hashlib.sha256()
with open(path, "rb") as f:
for chunk in iter(lambda: f.read(chunk_size), b""):
hasher.update(chunk)
return hasher.hexdigest()
def delete_duplicate_photos(directory):
directory …
How to Implement argparse CLI Command in Python
Build a beginner-friendly command-line tool with argparse that accepts positional and optional arguments, flags, and prints a customizable greeting.
import argparse
def main():
parser = argparse.ArgumentParser(description="A simple CLI tool to greet users.")
parser.add_argument("name", help="Your name")
parser.add_argument("-g", "--greeting", default="Hello", help="Greeting word (default: Hello)")
parser.add_argument("--uppercase", action="store_…
How to Import Users from CSV into LDAP-like Dicts in Python
Reads a CSV of user records and converts each row into an LDAP-style dictionary with standard attributes using Python's csv module.
import csv
import io
from pathlib import Path
def mock_ldap_import(csv_path):
"""
Reads a CSV file with user data and returns a list of LDAP-like user dicts.
Adds standard LDAP attributes that would come from directory schema.
"""
with open(csv_path, newline="", encoding="utf-8") as csvfile:
…
How to Kill Zombie Processes Matching a Name in Python
Scans running processes with ps, finds zombies whose command name matches a pattern, and attempts to kill them with SIGKILL.
import subprocess
import re
import signal
def find_zombies(name_pattern):
"""Find PIDs of zombie processes matching the given pattern."""
result = subprocess.run(["ps", "-eo", "pid,stat,comm"], capture_output=True, text=True)
zombies = []
for line in result.stdout.splitlines()[1:]: # Skip header
…
How to Map Network Drive Paths to Local Paths in Python
Convert mock SMB network drive paths (like 'S:\reports\q1.xlsx') to local placeholder paths and back using a simple mapping dictionary in Python.
"""Map mock SMB network drive paths to local placeholder paths."""
from dataclasses import dataclass
@dataclass(frozen=True)
class NetworkDrive:
letter: str
remote_path: str
DRIVES = {
"S:": NetworkDrive("S", r"\\server01\shares\sales"),
"M:": NetworkDrive("M", r"\\server02\media\movies"),
"X:": …
How to Merge PDFs in Python (Mock pypdf Stub)
Merge PDF files by concatenating their raw byte content using a simple stubbed class that mimics the pypdf interface.
import io
from hashlib import sha256
class PdfStub:
def __init__(self, data: bytes, name: str):
self.data = data
self.name = name
def get_content_bytes(self) -> bytes:
return self.data
def merge_pdfs_mock(pdf_stubs) -> bytes:
merged = io.BytesIO()
for stub in pdf_stubs:
…
How to Mock FFmpeg subprocess Calls in Python
Compress a video with ffmpeg while mocking subprocess.run to test the command construction without executing the actual encoder.
import subprocess
from unittest.mock import Mock, patch
def compress_video(input_path: str, output_path: str, crf: int = 23) -> None:
"""Compress a video using ffmpeg with a given CRF (quality) value."""
command = [
"ffmpeg",
"-i", input_path,
"-c:v", "libx264",
"-crf", str(cr…
How to Mock a Whisper API Transcription Stub in Python
Simulate an OpenAI Whisper-style transcription response with a dataclass request model and a mock function that returns structured audio transcription output.
import json
from dataclasses import dataclass
from typing import Optional
@dataclass
class AudioRequest:
file_path: str
language: Optional[str] = None
def to_api_payload(self) -> dict:
return {"file": self.file_path, "language": self.language}
def mock_whisper_transcribe(payload: dict) -> dict:
…
How to Mock an Ansible Inventory in Python
Load an Ansible-style inventory JSON file into Python and simulate a playbook run across hosts and groups.
import json
from pathlib import Path
class InventoryMock:
def __init__(self, inventory_file: str):
self.inventory_file = Path(inventory_file)
self.hosts = {}
def load(self):
if not self.inventory_file.exists():
raise FileNotFoundError(f"Inventory file {self.inventory_file…
How to Mock subprocess Calls in Python with unittest.mock
A Python script that wraps Vagrant up/destroy commands using subprocess, with tests that mock the subprocess call to simulate outputs and errors.
import subprocess
from unittest.mock import patch, Mock
def run_vagrant(action: str) -> str:
result = subprocess.run(
["vagrant", action],
capture_output=True,
text=True,
check=False,
)
return result.stdout.strip()
def vagrant_wrapper(action: str) -> str:
if action n…
How to Monitor Domain Expiration Dates in Python
A Python script that checks domain expiration dates using the python-whois library and warns when a domain is expiring soon.
import whois
from datetime import datetime, timedelta
import time
def check_domain_expiry(domain_name):
"""Check when a domain expires and warn if soon."""
try:
w = whois.whois(domain_name)
expiry = w.expiration_date
# Handle list or single date
if isinstance(expiry, list):
…
How to Monitor Process RSS Memory in Python
Poll the VmRSS field from /proc/PID/status to watch a process's resident memory and alert on growth.
import os
import time
import subprocess
import sys
def get_rss_mb(pid):
"""Return RSS memory in MB for a given process ID."""
try:
with open(f"/proc/{pid}/status", "r") as f:
for line in f:
if line.startswith("VmRSS:"):
return int(line.split()[1]) / 1024…
How to Parse CLI Arguments in Python with argparse
Build a beginner-friendly CLI with argparse that accepts optional --name, --greeting, and --uppercase flags, then prints a customizable greeting.
import argparse
def main():
parser = argparse.ArgumentParser(description="Greet a user with optional customization.")
parser.add_argument("--name", default="world", help="Name to greet")
parser.add_argument("--greeting", default="Hello", help="Greeting word")
parser.add_argument("--uppercase", action=…
How to Parse Terraform Plan Output in Python
Parse mock Terraform plan output text into structured add, change, and destroy lists using Python.
import json
from typing import Dict, List
def parse_terraform_plan_output(plan_output_text: str) -> Dict[str, List[str]]:
"""
Parses a mock Terraform plan output text into a structured dictionary.
"""
parsed: Dict[str, List[str]] = {"add": [], "change": [], "destroy": []}
for line in plan_output_…
How to Perform a DNS Lookup for A Records in Python
Resolve a hostname to IPv4 A records using Python's built-in socket.getaddrinfo and return a sorted list of addresses.
import socket
def get_a_records(hostname):
"""Fetch A records (IPv4 addresses) for a given hostname."""
try:
# getaddrinfo with family AF_INET restricts to IPv4 (A records)
infos = socket.getaddrinfo(hostname, None, socket.AF_INET)
# Each info tuple: (family, type, proto, canonname, so…
How to Quarantine Suspicious Files in Python
Move files with suspicious extensions to a quarantine folder using pathlib and shutil for safe isolation.
import shutil
import os
from pathlib import Path
def quarantine_files(source_dir, quarantine_dir, suspicious_extensions):
"""
Move files with suspicious extensions to a quarantine folder.
Returns list of moved files.
"""
source_path = Path(source_dir)
quarantine_path = Path(quarantine_dir)
…
How to Recover Deleted .txt Files from a Backup in Python
A Python function that searches a backup directory recursively and copies all .txt files to a destination folder, printing each recovered file name and a total count.
import os
import shutil
from pathlib import Path
def recover_deleted_txt_files(source_backup_dir: str, destination_dir: str) -> None:
"""Recover .txt files from backup directory."""
backup_path = Path(source_backup_dir)
dest_path = Path(destination_dir)
dest_path.mkdir(parents=True, exist_ok=True)
…
How to Resize Hundreds of Images in Batch with Python
Resize every image in a folder to a target size using Pillow, creating a new subfolder for processed files.
import os
from PIL import Image
def resize_images_in_batch(directory, output_size=(800, 600)):
if not os.path.exists(directory):
print(f"Directory {directory} does not exist.")
return
output_dir = os.path.join(directory, "resized")
os.makedirs(output_dir, exist_ok=True)
for filename in…
Browse by section
Each section groups closely related Python snippets.
Automation & scripting — Python code examples
What you will find here
This page collects automation & scripting snippets — short, copy-ready Python you can paste into our free online IDE and run without installing anything. Each sample includes a plain-English explanation and the full source code.
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.