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How to Deploy a Static Site Build to an Nginx Directory in Python
Copy a static site build directory into an Nginx web root using Python's shutil and pathlib modules.
import shutil
import os
from pathlib import Path
SRC_DIR = Path("build")
DEST_DIR = Path("/var/www/html")
def deploy_site(src: Path, dest: Path) -> None:
if not src.exists():
raise FileNotFoundError(f"Build directory not found: {src}")
dest.mkdir(parents=True, exist_ok=True)
for item in src.ite…How to Detect Applications Consuming Excessive Memory in Python
Use psutil to list the top memory-using processes by RSS and print their names, PIDs, and memory usage in MB.
import psutil
def find_top_memory_processes(limit=5):
"""Return top `limit` processes by memory usage (RSS)."""
processes = []
for proc in psutil.process_iter(['pid', 'name', 'memory_info']):
try:
info = proc.info
mem = info['memory_info'].rss if info['memory_info'] else 0…How to Detect Network Interface Changes in Python
Monitor active network interfaces and print a message when an interface is added or removed using psutil and socket.
import socket
import psutil
import time
def get_network_interfaces():
"""Return a set of currently active interface names."""
active_ifaces = set()
for iface, addrs in psutil.net_if_addrs().items():
for addr in addrs:
if addr.family == socket.AF_INET: # IPv4 address present
…How to Download a List of URLs to a Directory in Python
This script downloads a list of URLs into a specified directory, creating the folder if needed and keeping original filenames.
import urllib.request
from pathlib import Path
def download_urls(url_list, directory):
"""Download each URL in url_list into directory, keeping original filenames."""
save_dir = Path(directory)
save_dir.mkdir(parents=True, exist_ok=True)
for url in url_list:
filename = url.rstrip('/').spl…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 Dependency Graph for Python Projects
This script walks through a Python project directory, parses each .py file's imports, and prints a dependency graph showing which modules depend on which other modules.
import os
import ast
from pathlib import Path
from collections import defaultdict
def get_imports(filepath):
with open(filepath) as f:
try:
tree = ast.parse(f.read())
except SyntaxError:
return []
imports = []
for node in ast.walk(tree):
if isinstance(node, …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 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 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 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 Monitor USB Device Connections in Python
A Python utility that monitors USB device connections and disconnections by comparing output of the lsusb command at regular intervals.
import time
import subprocess
import os
def get_usb_devices():
"""Return list of currently connected USB devices (Linux)."""
try:
result = subprocess.run(['lsusb'], capture_output=True, text=True, check=True)
return result.stdout.strip().split('\n')
except (subprocess.CalledProcessError, F…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 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 Split PDF Pages into Ranges in Python
Simulates splitting a PDF into page ranges by validating and returning structured range splits for automation workflows.
import os
def split_pdf_ranges(pdf_name, num_pages, ranges):
"""
Simulates splitting a PDF by returning the page ranges that would be split.
Args:
pdf_name (str): Name of the PDF file.
num_pages (int): Total number of pages in the PDF.
ranges (list of tuple): List of (start, end) …How to Sync Two Directories in Python (rsync-like)
Mirror a source directory into a destination by copying new or changed files and deleting extras, similar to rsync.
import os
import shutil
import sys
from pathlib import Path
def sync_dirs(src: Path, dst: Path):
"""Mirror src into dst: copy new files, overwrite changed, delete extras."""
dst.mkdir(parents=True, exist_ok=True)
for dst_entry in dst.rglob('*'):
rel = dst_entry.relative_to(dst)
src_entry =…How to Tail and Colorize Error Lines in Python
Reads the last N lines of a log file and prints error lines in red using ANSI color codes.
import sys
import time
from pathlib import Path
def tail_colorize(filename: str, lines: int = 20) -> None:
"""Read last N lines of a file, printing errors in red."""
path = Path(filename)
if not path.exists():
print(f"File '{filename}' not found.", file=sys.stderr)
return
# Read last …How to automatically organize your Downloads folder by file type in Python
This script scans the Downloads folder and moves files into sub-folders based on their extensions (e.g., Images, Documents, Videos).
import os
import shutil
from pathlib import Path
def organize_downloads_folder(downloads_path=None):
if downloads_path is None:
downloads_path = str(Path.home() / "Downloads")
if not os.path.exists(downloads_path):
print(f"Path {downloads_path} does not exist.")
return
fi…How to check Python files for common coding mistakes
Walks a directory tree parsing each .py file with ast, reporting empty functions, bare try blocks, too many parameters, and empty classes.
import ast
import os
import sys
def check_file(filepath):
try:
with open(filepath) as f:
code = f.read()
tree = ast.parse(code, filename=filepath)
except SyntaxError as e:
print(f"{filepath}: SyntaxError: {e.msg}")
return
issues = []
for node in ast.wal…Mock Certbot Renewal in Python for Testing
Simulates a Let's Encrypt certificate renewal by writing a mock certificate file and printing realistic certbot CLI output, without calling the actual certbot.
import subprocess
import sys
from datetime import datetime, timedelta
from pathlib import Path
def renew_cert(domain: str, output_dir: str = "certs") -> str:
"""Simulate a Let's Encrypt renewal with mock certbot output."""
out = Path(output_dir)
out.mkdir(parents=True, exist_ok=True)
cert_path = out…Pin Python package versions in requirements.txt
Pin package versions in requirements.txt-style text by adding ==version when no specifier is present, while preserving existing version constraints and comments.
import re
from pathlib import Path
def pin_versions(requirements_text: str) -> str:
"""
Pin package versions in requirements.txt-style text.
Adds ==version if no version specifier is present.
Keeps existing specifiers (>=, <=, ~=, etc.) unchanged.
"""
lines = requirements_text.strip().splitli…Port Scan Localhost Common Ports in Python
Scan common localhost ports (HTTP, HTTPS, SSH, FTP, and more) with a fast socket-based Python script that prints an open/closed status table.
import socket
from datetime import datetime
COMMON_PORTS = {
80: "HTTP",
443: "HTTPS",
22: "SSH",
21: "FTP",
25: "SMTP",
3306: "MySQL",
5432: "PostgreSQL"
}
def scan_port(port):
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sock.settimeout(0.1)
try:
resu…Post a message to a Slack webhook in Python
Send a message to a Slack webhook endpoint using the standard library's urllib.request, handling the POST request and response cleanly.
import json
from urllib import request
def post_to_slack(webhook_url: str, message: str) -> dict:
payload = json.dumps({"text": message}).encode("utf-8")
req = request.Request(
webhook_url,
data=payload,
headers={"Content-Type": "application/json"},
method="POST",
)
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