Lesson 6 of 19

Functions

Group reusable logic into named functions.

Introduction

Functions make programs easier to organize, test and reuse.

Python defines functions with the def keyword and can return values to the calling code.

Key insight

Example

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

print(greet("Asha"))

This example shows the core functions idea in a small, runnable program.

Real-world example

Test yourself

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Answer every question, then submit your quiz.

Try it yourself

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Output appears here

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Practice challenge

Write a function that returns the square of a number.