def

Learn to define functions with def.

Defining functions with def

A function is a reusable block of code. It is defined with the def keyword:

def greet():
    print("Welcome")

The function body is indented; this is how Python marks a block. The function is called with greet().

Functions prevent code repetition and split a program into parts. This improves both readability and maintainability.

A defined function is run by calling its name with parentheses:

def greet():
    print("Welcome")

greet()   # Welcome

Without parentheses, greet just refers to the function object; it does not call it. This is a common mistake.

You can call a function as many times as you like; this prevents code repetition.

Define a function called greet that prints print("Welcome"). Then call it with greet().

Show example solution

def greet():
    print("Welcome")
greet()

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