Creating Functions

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

greet()  # Call the function

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

greet("Alice")

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

result = add(5, 3)  # result = 8

def calculate_total(price, tax_rate):
    tax = price * tax_rate
    return price + tax

total = calculate_total(100, 0.08)  # 108

def check_grade(score):
    if score >= 90:
        return "A"
    elif score >= 80:
        return "B"
    else:
        return "C"

grade = check_grade(95)  # "A"

def area_of_circle(radius):
    return 3.14 * radius * radius