Converting Python 2.x code to Python 3.x code
---------------------------------------------

Since Python 2.6, Python has include a standard tool 2to3 to assist in the conversion.
http://docs.python.org/library/2to3.html

Program features that need to be changed
  * has_key changed to x in dict
  * apply() removed
  * reduce() changed to functools.reduce()

Infrastructure for automatic refactoring
  * tokenize module
  * Python 2.5 compile() return ast objects