Python is a typical interpreted language. (It tokenizes the code at program start-up. It does not JIT.) Python is thus adequately fast for simple things, but poorly suited to tasks such as number crunching. Processor intensive tasks are usually handled by a lower level language (normally C). The biggest advantage for the project is that source code is naturally supplied to the user, making Open Source software licenses easy to satisfy and making code available for children to modify. The biggest advantage for activity developers is that Python libraries are supplied which encapsulate the sugar API
 Obtaining and learning Python
Python is commonly provided by default on Linux and BSD systems. OLPC is currently using version 2.5 on the XO.
You can download nicely packaged Python called ActivePython. They proclaim themselves as the All-in-one Python distribution for AIX, HP-UX, Linux, Mac OS X, Solaris, and Windows.
PyGTK is the Python interface to the GTK GUI library used in the OLPC. This library is notable for a component named Pango which simplifies the use of multiple scripts and languages. In addition, it's basic drawing library, Cairo, has some of the best support of SVG rendering which is also a major component of the OLPC.
The Livewires Python Course may be useful to create some curriculum material to teach the kids how to write their own Python applications. It would need some adaptation to fit the OLPC environment.
The author of Python wrote a long tutorial.
 Development Advice
Some things to consider in Python development:
- PEP 8 is the Python style guide. On many issues the style guide suggests but does not require a particular style. Generally you should stick to the style guide, unless there is good reason not to. For instance, if you are interacting with a library (internal or external) that uses a different convention, don't try to translate the convention.