Your best way to get started with Python on Mac OS X is through the IDLE integrated development environment, see section 1.2 and use the Help menu when the IDE is running.
If you want to run Python scripts from the Terminal window command line or from the Finder you first need an editor to create your script. Mac OS X comes with a number of standard Unix command line editors, vim and emacs among them. If you want a more Mac-like editor, BBEdit or TextWrangler from Bare Bones Software (see http://www.barebones.com/products/bbedit/index.shtml) are good choices, as is TextMate (see http://macromates.com/). Other editors include Gvim (http://macvim.org) and Aquamacs (http://aquamacs.org).
To run your script from the Terminal window you must make sure that /usr/local/bin is in your shell search path.
To run your script from the Finder you have two options:
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