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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 print_licences(params, metadata):
 """Print licenses. :param argparse.Namespace params: parameter :param bootstrap_py.classifier.Classifiers metadata: package metadata """

    if hasattr(params, 'licenses'):
        if params.licenses:
            _pp(metadata.licenses_desc())
        sys.exit(0)