What does += mean in Python?

Question

I see code like this for example in Python:

    if cnt > 0 and len(aStr) > 1:
        while cnt > 0:                  
            aStr = aStr[1:]+a         


        

Answer 1

Google 'python += operator' leads you to http://docs.python.org/library/operator.html

Search for += once the page loads up for a more detailed answer.