Python on OS X honors all standard Unix environment variables such as PYTHONPATH, but setting these variables for programs started from the Finder is non-standard as the Finder does not read your .profile or .cshrc at startup. You need to create a file ~ /.MacOSX/environment.plist. See Apple's Technical Document QA1067 for details.
For more information on installation Python packages in MacPython, see section 1.3, ``Installing Additional Python Packages.''
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