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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 safe_version(version):
 """ Convert an arbitrary string to a standard version string """

    try:
        # normalize the version
        return str(packaging.version.Version(version))
    except packaging.version.InvalidVersion:
        version = version.replace(' ', '.')
        return re.sub('[^A-Za-z0-9.]+', '-', version)