Creating simple Python calculator

Hi guys, I am relatively new to Python and have been working on a calculator application. It is relatively simple, but I would like to share it with everyone here in the group. I hope that there is someone in Daniweb who can guide me through Python.
As I read about Python, it is among the top three programming languages, and has many areas of use.
My background is in Electrical engineering, and I hope to use Python for some purpose in electrical engineering.
Please feel free to make any suggestions or improvements to the code.

# Program make a simple calculator

# 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 your operation.")
print("1.Add")
print("2.Subtract")
print("3.Multiply")
print("4.Divide")

while True:
    # take input from the user
    choice = input("Enter your choice(1/2/3/4): ")

    # check if choice is one of the four options
    if choice in ('1', '2', '3', '4'):
        num1 = float(input("Enter the first number: "))
        num2 = float(input("Enter the second number: "))

        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("Wanna do another calculation? (y/n): ")
        if next_calculation == "no":
          break

    else:
        print("Invalid Input")