Python for a Perl programmer

I've recently had to make a similar transition for work reasons, and it's been pretty painful. For better or worse, Python has a very different philosophy and way of working than Perl, and getting used to that can be frustrating. The things I've found most useful have been

• Spend a few hours going through all the basics. I found the official tutorial quite good, if a little dry.
• A good reference book to look up basic stuff ("how do I get the length of a string again?"). The ones I've found most useful are the Python Pocket Reference and Python Essential Reference.
• Take a look at this handy Perl<->Python phrasebook (common tasks, side by side, in both languages).
• A reference for the Python approach to "common tasks". I use the Python Cookbook.
• An ipython terminal open at all times to test syntax, introspect object methods etc.
• Get pip and easy-install (to install Python modules easily).
• Learn about unit tests fast. This is because without use strict you will feel crippled, and you will make many elementary mistakes which will appear as runtime errors. I recommend nose rather than the unittest framework that comes with the core install. unittest is very verbose if you're used to Test::More.
• Check out Python questions on Stack Overflow. In particular, Python - Things one MUST avoid and Python 2.x gotcha’s and landmines are well worth a read.

Personally, I found Dive Into Python annoying and patronising, but it's freely available online, so you can form your own judgment on that.

If you happen to be a fan of The Perl Cookbook, you might be interested in checking out PLEAC, the Programming Language Examples Alike Cookbook, specifically the section that shows the Perl Cookbook code translated into Python.

Being a hardcore Perl programmer, all I can say is DO NOT BUY O'Reilly's "Learning Python". It is nowhere NEAR as good as "Learning Perl", and there's no equivalent I know of to Larry Wall's "Programming Perl", which is simply unbeatable.

I've had the most success taking past Perl programs and translating them into Python, trying to make use of as many new techniques as possible.