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Functions & basics

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

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How to Write a Python Decorator with functools.wraps

Create a decorator that wraps a function while preserving its metadata using functools.wraps.

from functools import wraps


def logger(func):
    @wraps(func)
    def wrapper(*args, **kwargs):
        print(f"Calling {func.__name__}")
        return func(*args, **kwargs)
    return wrapper


@logger
def greet(name):
    """Return a friendly greeting."""
    return f"Hello, {name}!"


if __name__ == "__main__":…

12 0 Open

Functions & basics easy

How to implement binary search in Python

Standalone binary search function that returns the index of a target in a sorted list, or -1 if not found.

binary search algorithms search

Python

def binary_search(arr, target):
    left, right = 0, len(arr) - 1
    
    while left <= right:
        mid = (left + right) // 2
        if arr[mid] == target:
            return mid
        elif arr[mid] < target:
            left = mid + 1
        else:
            right = mid - 1
    
    return -1

if __name__ ==…

13 0 Open

Functions & basics easy

How to measure function memory with sys.getsizeof in Python

Measure the memory footprint of Python functions (user-defined and built-in) using sys.getsizeof.

sys getsizeof memory

Python

import sys

def sample_function(a, b, c):
    return a + b - c

def measure_function_memory(func):
    size = sys.getsizeof(func)
    print(f"Memory size of {func.__name__}: {size} bytes")

if __name__ == "__main__":
    measure_function_memory(sample_function)
    measure_function_memory(print)
    measure_function_m…

13 0 Open

Functions & basics easy

How to use function defaults in Python

Define Python functions with default parameter values so callers can omit arguments and use sensible fallbacks.

functions default-parameters basics

Python

def greet(name="Guest", greeting="Hello", punctuation="!"):
    """Return a greeting message using default parameters."""
    return f"{greeting}, {name}{punctuation}"

def describe_pet(pet_name, animal_type="dog"):
    """Display information about a pet with a default animal type."""
    print(f"I have a {animal_type…

15 0 Open

Functions & basics easy

Python Function Default Parameters Explained with Examples

Learn how to define Python functions with default parameter values and call them with fewer arguments than declared.

functions default-parameters args

Python

def greet(name, greeting="Hello", punctuation="!"):
    return f"{greeting}, {name}{punctuation}"

def calculate_area(length, width=1, unit="sq units"):
    area = length * width
    return f"Area: {area} {unit}"

if __name__ == "__main__":
    print(greet("Alice"))
    print(greet("Bob", "Hi"))
    print(greet("Charl…

14 0 Open

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