🧠 Python Tutorial: Understanding Functions in Python

Introduction

Functions are reusable blocks of code that perform specific tasks. They help you organize your code, reduce repetition, and improve readability.

1. Defining a Function

def greet():
    print("Hello, Koikoi!")

Try it yourself: Define a function that prints your favorite quote.

2. Calling a Function

greet()

Exercise: Call your custom function and observe the output.

3. Function with Parameters

def greet_user(name):
    print("Hello,", name)

greet_user("Benjamin")

Challenge: Pass different names to your function.

4. Returning Values

def add(a, b):
    return a + b

result = add(5, 3)
print(result)

Try it: Create a function that returns the square of a number.

5. Real‑World Example: Calculator

def calculator(a, b, operation):
    if operation == "add":
        return a + b
    elif operation == "subtract":
        return a - b
    else:
        return "Invalid operation"

print(calculator(10, 5, "add"))

Challenge: Add support for multiplication and division.

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Want to dive deeper? Check out these related tutorials:
➡ Python Dictionaries Explained
➡ Python Lists Explained
➡ Python Interactive Tutorial: From Basics to Mastery

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