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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _os_x_font_directories(cls):
 """ Return a sequence of directory paths on a Mac in which fonts are likely to be located. """

        os_x_font_dirs = [
            '/Library/Fonts',
            '/Network/Library/Fonts',
            '/System/Library/Fonts',
        ]
        home = os.environ.get('HOME')
        if home is not None:
            os_x_font_dirs.extend([
                os.path.join(home, 'Library', 'Fonts'),
                os.path.join(home, '.fonts')
            ])
        return os_x_font_dirs