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Functions & basics

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

3 matches

Add Type Hints to Function Parameters and Return in Python

Add type hints to function parameters and return values in Python for clearer, more maintainable code using the typing module.

type-hints typing annotations

Python

from typing import List, Optional, Dict


def average(numbers: List[float]) -> float:
    return sum(numbers) / len(numbers)


def full_name(first: str, last: Optional[str] = "") -> str:
    return f"{first} {last}".strip()


def build_user(name: str, age: int, email: Optional[str] = None) -> Dict[str, object]:
    us…

15 0 Open

Functions & basics easy

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 Write a Normalize Function with Default Parameters in Python

Define a reusable normalize function with configurable default parameters for lowercase conversion, whitespace stripping, and punctuation removal.

functions default-parameters string-processing

Python

def normalize(text, lowercase=True, strip_whitespace=True, remove_punctuation=False):
    """Normalize a string based on configurable options."""
    if lowercase:
        text = text.lower()
    if strip_whitespace:
        text = text.strip()
    if remove_punctuation:
        text = ''.join(char for char in text if…

13 0 Open

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