Key differences between Python 2.7.x and Python 3.x
Just a short list, not too bad. The __future__ module The print function Integer division Unicode xrange Raising exceptions Handling exceptions The next() function and .next() method For-loop variables and the global namespace leak Comparing unorderable types Parsing user inputs via input() Returning iterable objects instead of lists Banker’s Rounding http://sebastianraschka.com/Articles/2014_python_2_3_key_diff.html