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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 list_styles(self):
 """Print available styles and exit. """

        known = sorted(self.defaults.known_styles)
        if not known:
            err_exit('No styles', 0)
        for style in known:
            if style == self.defaults.default_style:
                print(style, '(default)')
            else:
                print(style)
        sys.exit(0)