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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 export_cmd(argv=sys.argv[1:]):
 # pragma: no cover """\ Export a model from one model persister to another. The model persister to export to is supposed to be available in the configuration file under the 'model_persister_export' key. Usage: pld-export [options] Options: --version=<v> Export a specific version rather than the active one. --no-activate Don't activate the exported model with the 'model_persister_export'. -h --help Show this screen. """

    arguments = docopt(export_cmd.__doc__, argv=argv)
    model_version = export(
        model_version=arguments['--version'],
        activate=not arguments['--no-activate'],
        )
    logger.info("Exported model. New version number: {}".format(model_version))