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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(conf):
 """The fedora-messaging command line interface."""

    if conf:
        if not os.path.isfile(conf):
            raise click.exceptions.BadParameter("{} is not a file".format(conf))
        try:
            config.conf.load_config(config_path=conf)
        except exceptions.ConfigurationException as e:
            raise click.exceptions.BadParameter(str(e))
    twisted_observer = legacy_twisted_log.PythonLoggingObserver()
    twisted_observer.start()
    config.conf.setup_logging()