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Functions & basics

Reusable building blocks — parameters, returns, scope, and clear function design.

3 matches

Format CLI help text in Python

Build a readable usage string for a command-line tool, aligning flags and wrapping descriptions with the textwrap module.

cli textwrap formatting

Python

import textwrap


def format_help(command_name: str, description: str, options: list[tuple[str, str]]) -> str:
    """Format CLI help text into a readable usage string."""
    header = f"Usage: {command_name} [OPTIONS]"
    lines = [header, "", description, "", "Options:"]

    for flag, help_text in options:
        …

12 0 Open

Functions & basics easy

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.

argparse cli dry-run

Python

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…

11 0 Open

Functions & basics easy

How to Use the if name == 'main' Guard in Python

This code defines reusable functions and uses the standard main guard to run them only when the script is executed directly, not when imported.

main guard __main__ script entry point

Python

def greet(name: str) -> str:
    """Return a friendly greeting."""
    return f"Hello, {name}!"

def get_planet() -> str:
    """Return the name of our planet."""
    return "Earth"

if __name__ == "__main__":
    user = "Dorothy"
    print(greet(user))
    print(f"We live on {get_planet()}.")

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