Python version differences

Question

I got a book for python 2.5 but up until now I've been using 2.7. Will there be any huge barriers to overcome?

Answer 1

No, Python 2.7 is compatible with 2.5. There were a few features that were added, but everything you learned from 2.5 should work in 2.7.

Python 3, on the other hand, makes some big changes that are not compatible with 2.5.

Answer 2

The 2.x versions are (generally - if 2.x had a bug somewhere and some fool writes code that takes this incorrect behaviour for granted, upgrade to 2.(x+1) will of course change the behaviour) backwards-compatible. So the examples written for 2.5 should run fine for 2.7.

Note though that you're missing out several cool features added in 2.6 and 2.7, including with statements for easy resource management and more, new string formatting, new kinds of integer literals, dictionary and set comprehensions. Also countless improved and new modules.