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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 cli(self, cmd_args=None):
 """ The command line interface of PyGreen. """

        logging.basicConfig(level=logging.INFO, format='%(message)s')

        parser = argparse.ArgumentParser(description='PyGreen, micro web framework/static web site generator')
        subparsers = parser.add_subparsers(dest='action')

        parser_serve = subparsers.add_parser('serve', help='serve the web site')
        parser_serve.add_argument('-p', '--port', type=int, default=8080, help='port to serve on')
        parser_serve.add_argument('-f', '--folder', default=".", help='folder containg files to serve')
        parser_serve.add_argument('-d', '--disable-templates', action='store_true', default=False, help='just serve static files, do not use Mako')
        def serve():
            if args.disable_templates:
                self.template_exts = set([])
            self.run(port=args.port)
        parser_serve.set_defaults(func=serve)

        parser_gen = subparsers.add_parser('gen', help='generate a static version of the site')
        parser_gen.add_argument('output', help='folder to store the files')
        parser_gen.add_argument('-f', '--folder', default=".", help='folder containing files to generate')
        def gen():
            self.gen_static(args.output)
        parser_gen.set_defaults(func=gen)

        args = parser.parse_args(cmd_args)
        self.set_folder(args.folder)
        print(parser.description)
        print("")
        args.func()