Functions - Your Code Helpers

Understanding the Concept

Functions are like having helpful assistants that do specific jobs for you! Instead of writing the same code over and over, you create a function once and call it whenever you need it. Think of it like a recipe - you write it once, but you can cook the dish many times. Functions make your code organized, reusable, and way less repetitive!

Code Example

# Create a simple function
def greet_user(name):
    print(f"Hello, {name}! Welcome to Python!")
    
# Use (call) your function
greet_user("Alex")
greet_user("Sam")

# Function that returns a value
def add_numbers(a, b):
    result = a + b
    return result

sum_result = add_numbers(5, 3)
print("Sum is:", sum_result)

💡 Explanation: Use 'def' to create functions. They can take inputs (parameters) and give back outputs (return values). Call them by using their name with parentheses!

Quick Actions

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Your Turn to Practice

Create a function called 'square_number' that takes a number and returns its square. Then test it with a few different numbers!

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Knowledge Check

Key Topics

function def return parameter argument call invoke helper reuse

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