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How to Add a Dry Run Flag to a Python CLI Command
Build a Python CLI command with a --dry-run flag that previews actions and exits before making real changes.
import argparse
import sys
def main():
parser = argparse.ArgumentParser(description="Sample CLI command with dry-run flag")
parser.add_argument("--name", required=True, help="Name to greet")
parser.add_argument("--dry-run", action="store_true", dest="dry_run",
help="Show what would…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.")
…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.…Fetch weather API mock and write dashboard HTML in Python
This script fetches a mock weather API response as a Python dict, builds a simple HTML dashboard, writes it to a file, and prints both the file path and JSON payload.
from datetime import datetime
import json
import os
def fetch_weather_mock(city: str) -> dict:
"""Return a mock weather payload for a given city."""
return {
"city": city,
"temperature_c": 21.5,
"condition": "Partly Cloudy",
"humidity": 58,
"wind_kph": 12.3,
"u…How to Build a CLI with argparse in Python
Create a beginner-friendly command-line tool in Python that processes multiple filenames with optional flags for verbose output and uppercase conversion.
import argparse
def main():
parser = argparse.ArgumentParser(
description="A simple CLI to process files with optional verbose mode."
)
parser.add_argument("filenames", nargs="+", help="Files to process")
parser.add_argument("-v", "--verbose", action="store_true", help="Print extra details")
…How to Build a Docker Image Tag Script in Python
Generate consistent Docker image tags from service names and versions with automatic normalization.
#!/usr/bin/env python3
"""Mock script for building docker image tags."""
def build_tag(service_name: str, version: str, registry: str = "docker.io") -> str:
"""Construct a docker image tag."""
safe_name = service_name.lower().replace("_", "-")
return f"{registry}/{safe_name}:{version}"
if __name__ == "…How to Build a Simple Python CLI with argparse
Create a friendly command-line greeting tool with argparse that accepts a positional name and optional flags for custom greetings and uppercase output.
import argparse
def greet(name, greeting="Hello", uppercase=False):
message = f"{greeting}, {name}!"
return message.upper() if uppercase else message
if __name__ == "__main__":
parser = argparse.ArgumentParser(
description="A simple greeting tool to demonstrate argparse basics."
)
parser.…How to Build a Simple argparse CLI in Python
Create a beginner-friendly command-line tool with argparse that reads a file, optionally uppercases its lines, and prints a configurable number of lines.
import argparse
def main():
parser = argparse.ArgumentParser(
description="Automate file processing with a simple CLI tool."
)
parser.add_argument("filename", help="Path to the input file")
parser.add_argument("--uppercase", action="store_true", help="Convert text to uppercase")
parser.add…How to Build a Simple argparse CLI in Python
Build a beginner-friendly command-line tool with argparse that greets a user, with optional greeting text and uppercase output.
import argparse
def greet(name, greeting="Hello", uppercase=False):
message = f"{greeting}, {name}!"
if uppercase:
message = message.upper()
return message
if __name__ == "__main__":
parser = argparse.ArgumentParser(description="Simple CLI greeting tool")
parser.add_argument("name", help=…How to Create a Simple Python CLI with argparse
Build a beginner-friendly command-line tool with argparse that accepts positional and optional arguments to greet users flexibly.
import argparse
def greet(name, greeting="Hello", uppercase=False):
message = f"{greeting}, {name}!"
return message.upper() if uppercase else message
def main():
parser = argparse.ArgumentParser(
description="A simple CLI tool that greets users."
)
parser.add_argument(
"name",
…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 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 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 Simulate a Traceroute in Python
This Python script simulates a network traceroute by generating mock hop IPs, random delays, and a destination reach condition, useful for testing network scripts.
import random
import time
def simulate_traceroute(destination, max_hops=30):
"""Simulate a traceroute to a destination with mock hop delays."""
print(f"Traceroute to {destination} ({max_hops} hops max):")
for hop in range(1, max_hops + 1):
# Mock IP address for the hop
mock_ip = f"10.0.{ra…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 Write an IP Block List to hosts.deny in Python
This Python script validates a list of IP addresses and CIDR ranges, then writes them to a hosts.deny file to block connections at the TCP wrapper level.
from ipaddress import ip_network
def write_hosts_deny(ip_list, output_file="hosts.deny"):
with open(output_file, "w") as f:
for ip in ip_list:
try:
ip_network(ip)
f.write(f"ALL: {ip}\n")
except ValueError:
continue
print(f"Written…Monitor Disk Usage and Alert in Python
A Python script that checks disk usage percentage against a threshold and returns an ALERT or OK message with free space details.
import shutil
import os
def check_disk_usage(path="/", threshold=85.0):
usage = shutil.disk_usage(path)
percent_used = (usage.used / usage.total) * 100
if percent_used > threshold:
return (f"ALERT: Disk usage at {percent_used:.1f}% on {path} "
f"(exceeds {threshold}% threshold…Rename Files in Folder with Numeric Prefix in Python
Renames all files in a folder by adding a sequential numeric prefix (e.g., 01_, 02_) to each filename using pathlib.
from pathlib import Path
def rename_with_numeric_prefix(folder_path):
folder = Path(folder_path)
for index, file_path in enumerate(folder.iterdir(), start=1):
if file_path.is_file():
new_name = f"{index:02d}_{file_path.name}"
new_path = file_path.with_name(new_name)
…Stress CPU Threads with a Mock Compute in Python
Simulates CPU-intensive work across multiple threads to test how Python schedules parallel compute.
import threading
import time
def stress_cpu(iterations: int):
result = 0
for i in range(iterations):
result += i * i % 1000
return result
def run_mock_stress(thread_count: int, iterations: int):
threads = []
for tid in range(thread_count):
t = threading.Thread(target=lambda: str…Toggle VPN Mock Network Manager Script in Python
Simulate a VPN manager with connect, disconnect, toggle, and status methods for testing or demo workflows.
import time
class MockVPNManager:
def __init__(self):
self.is_connected = False
self.servers = ["us-west", "eu-central", "asia-east"]
self.active_server = None
def toggle(self):
if self.is_connected:
self.disconnect()
else:
self.connect()
d…Bisect Good Bad Automation Script in Python
This Python script implements a binary search to find the first bad version in a list, simulating an automation script for git bisect.
import bisect
def find_first_bad(versions):
"""Given a list of version objects with .is_bad(), find first bad version."""
lo, hi = 0, len(versions)
while lo < hi:
mid = (lo + hi) // 2
if versions[mid].is_bad():
hi = mid
else:
lo = mid + 1
return lo
clas…How to Auto-Suggest a SemVer Bump From Git Commit Messages in Python
This code scans Git commit messages (recent or sample) and suggests the next Semantic Versioning bump type — major, minor, patch, or none.
import re
import subprocess
from pathlib import Path
def get_commit_messages(path="."):
"""Read commit messages from a repo or use sample messages."""
if (Path(path) / ".git").exists():
out = subprocess.run(
["git", "-C", path, "log", "--pretty=%s"], capture_output=True, text=True
…How to Create a Git Branch if it Doesn't Exist in Python
Utility script that checks if a Git branch exists locally and either creates it or checks it out, with error handling.
import subprocess
import sys
def ensure_branch(branch_name):
"""Create a Git branch if it doesn't exist, otherwise checkout it."""
try:
# Check if the branch exists locally
result = subprocess.run(
["git", "branch", "--list", branch_name],
capture_output=True,
…How to Create a Git Commit with Message Template in Python
Run a git commit from Python using a standardized message template built from a commit type and description.
import subprocess
import sys
def commit_with_template(commit_type: str, description: str) -> None:
message = f"{commit_type}: {description}"
try:
subprocess.run(["git", "commit", "-m", message], check=True)
print(f"Committed: {message}")
except subprocess.CalledProcessError as e:
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