Python: x += 1 vs x = x + 1

[pramodliv1]

http://stackoverflow.com/questions/15376509/when-is-i-x-different-from-i-i-x-in-python

[ColinWright]

The title here is neither the question being asked, nor the question being answered, and hence is significantly misleading given the fact that this is a detailed question about a detailed aspect of behavior.