This function adds two numbers

def add(x, y):

return x + y

This function subtracts two numbers

def subtract(x, y):

return x - y

This function multiplies two numbers

def multiply(x, y):

return x * y

This function divides two numbers

def divide(x, y):

return x / y

print("Select operation.")

print("1.Add")

print("2.Subtract")

print("3.Multiply")

print("4.Divide")

while True:

# take input from the user

choice = input("Enter choice(1/2/3/4): ")



# check if choice is one of the four options

if choice in ('1', '2', '3', '4'):

    try:

        num1 = float(input("Enter first number: "))

        num2 = float(input("Enter second number: "))

    except ValueError:

        print("Invalid input. Please enter a number.")

        continue



    if choice == '1':

        print(num1, "+", num2, "=", add(num1, num2))



    elif choice == '2':

        print(num1, "-", num2, "=", subtract(num1, num2))



    elif choice == '3':

        print(num1, "*", num2, "=", multiply(num1, num2))



    elif choice == '4':

        print(num1, "/", num2, "=", divide(num1, num2))

    

    # check if user wants another calculation

    # break the while loop if answer is no

    next_calculation = input("Let's do next calculation? (yes/no): ")

    if next_calculation == "no":

      break

else:

    print("Invalid Input")