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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 get_version_name(version_id):
 """ Get the name of a protocol version by the internal version ID. :param Integer version_id: Internal protocol version ID :return: Name of the version :rtype: String """

    ver = registry.version_info.get(version_id)
    if ver:
        return ver.name

    return 'unknown'