There are two ways to simulate command-line arguments with MacPython.
via Interpreter options
Hold the option-key down when launching your script. This will
bring up a dialog box of Python Interpreter options.
Click ``Set Unix-style command line..'' button.
Type the arguments into the ``Argument'' field.
Click ``OK''
Click ``Run''.
via drag and drop
If you save the script as an applet (see Section 1.6.4), you
can also simulate some command-line arguments via
``Drag-and-Drop''. In this case, the names of the files that were
dropped onto the applet will be appended to sys.argv, so that
it will appear to the script as though they had been typed on a
command line. As on Unix systems, the first item in sys.srgv is
the path to the applet, and the rest are the files dropped on the
applet.