Basic addition with Python, numbers don't add
Question: I'm pretty new to Python and I was trying to make a basic addition program.
Here is the source so far:

    
    
    from os import system
    import time
    
    while True:
        system("cls")
        print "Number 1:"
        num1 = raw_input()
        system("cls")
        print "Number 2:"
        num2 = raw_input()
        system("cls")
        sum = num1 + num2
        print sum
        time.sleep(4)
    

It just puts num1 and num2 together instead of actually adding the numbers.
Like if I put 4 + 4 it'd do 44 instead of 8. I understand WHY it does this I
just want to know how to fix it.


Answer: You are summing strings, which results in concatenation, while you want to
treat the values as _numbers_ instead. Convert the string to a number first.

Use the [`int()`
function](https://docs.python.org/2/library/functions.html#int) to convert to
integer numbers, for example:

    
    
    num1 = int(raw_input())
    # ...
    num2 = int(raw_input())
    

