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

greet()

Hello, Sara!

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

add(5, 3)

8

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

def greet_name(name):
    print(f"Hi {name}!")

def square(x):
    return x * x

def welcome(name="Sara"):
    print(f"Welcome, {name}!")

def intro(name, age):
    print(f"{name} is {age} years old")

intro(age=21, name="Sara")

Sara is 21 years old

def total(*nums):
    print(sum(nums))

total(1, 2, 3, 4)

10

def student_details(**kwargs):
    for key, value in kwargs.items():
        print(f"{key}: {value}")

student_details(name="Sara", age=20, course="AI")

name: Sara
age: 20
course: AI

x = 10
def func():
    x = 5
    print("Inside:", x)

func()
print("Outside:", x)

Inside: 5
Outside: 10

x = 10
def update():
    global x
    x = 20

update()
print("Now x:", x)

Now x: 20

square = lambda x: x * x
print(square(6))

36

add = lambda a, b: a + b
add(2, 3)

5

nums = [1, 2, 3, 4]
squares = list(map(lambda x: x**2, nums))
print(squares)

[1, 4, 9, 16]

evens = list(filter(lambda x: x % 2 == 0, nums))
print(evens)

[2, 4]

from functools import reduce
total = reduce(lambda a, b: a + b, nums)
print(total)

10

# Mini calculator
def calc(a, b, op):
    if op == '+': return a + b
    elif op == '-': return a - b
    elif op == '*': return a * b
    elif op == '/': return a / b
    else: return "Invalid"

calc(10, 5, '*')

50

# Use input + call functions
def main():
    a = int(input("Enter a: "))
    b = int(input("Enter b: "))
    op = input("Enter operator (+ - * /): ")
    print("Result:", calc(a, b, op))

main() 

Enter a:  2
Enter b:  2
Enter operator (+ - * /):  +


Result: 4