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Functions & basics

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

4 matches

How to Build Partial Functions with functools.partial in Python

Create reusable partial functions that pre-fill arguments using functools.partial, like making square and cube functions from a general power function.

functools partial higher-order-functions

Python

```python
from functools import partial

def power(base, exponent):
    """Calculate base raised to the exponent power."""
    return base ** exponent

# Create partial functions for common powers
square = partial(power, exponent=2)
cube = partial(power, exponent=3)

if __name__ == "__main__":
    squares = [square(x)…

12 0 Open

Functions & basics easy

How to Create a Higher-Order Function in Python (Apply Twice)

This code defines a higher-order function that takes another function and a value, then applies the function twice to the value and returns the result.

higher-order functions composition

Python

def apply_twice(func, value):
    return func(func(value))

def add_ten(x):
    return x + 10

def square(x):
    return x ** 2

if __name__ == "__main__":
    print(apply_twice(add_ten, 5))
    print(apply_twice(square, 3))

12 0 Open

Functions & basics easy

How to Sort a List of Numbers in Python with Default Parameters

Define a reusable sort function that uses a default parameter to sort a list of numbers in ascending or descending order.

sorting default-parameters functions

Python

def sort_numbers(numbers, reverse=False):
    """Sort a list of numbers in ascending or descending order."""
    return sorted(numbers, reverse=reverse)


def main():
    numbers = [5, 2, 9, 1, 7, 3]
    
    # Default sort (ascending)
    ascending = sort_numbers(numbers)
    print(f"Ascending: {ascending}")
    
   …

13 0 Open

Functions & basics easy

Sort a List of Dictionaries by Key in Python

Uses a lambda function with sorted() to order a list of dictionaries by a specified key, like price.

lambda sorting list

Python

def get_items():
    return [
        {"name": "apple", "price": 3},
        {"name": "banana", "price": 1},
        {"name": "cherry", "price": 2},
    ]

if __name__ == "__main__":
    items = get_items()
    sorted_items = sorted(items, key=lambda item: item["price"])
    for item in sorted_items:
        print(f"{…

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