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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 parse_command_line() -> Namespace: """Parse command line options and set them to ``config``. This function skips unknown command line options. After parsing options, set log level and set options in ``tornado.options``. """

    import tornado.options
    parser.parse_known_args(namespace=config)
    set_loglevel()  # set new log level based on commanline option
    for k, v in vars(config).items():
        if k.startswith('log'):
            tornado.options.options.__setattr__(k, v)
    return config