Python: Visual QuickStart Guide, Second Edition

Appendix B. Comparing Python 2 and Python 3

Python 3 was released at the end of 2008 and marks a major update to Python. Some of the changes introduced in Python 3 break backward compatibility with earlier versions of Python, so to ease the transition for current Python developers, the development of Python 2 has continued in parallel with the newer Python 3.

In this chapter, we’ll summarize some of the main changes to Python 3 and also explain how you can convert a Python 2 program to Python 3.

What’s New in Python 3

Python 3 introduces many new features; the following are some of the most visible:

• Python 3’s print function is indeed a function. In Python 2, print was a language construct, similar to if and for. The problem with Python 2’s print ...