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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 clean(config):
 """ Delete a wily cache. :param config: The configuration :type config: :class:`wily.config.WilyConfig` """

    if not exists(config):
        logger.debug("Wily cache does not exist, skipping")
        return
    shutil.rmtree(config.cache_path)
    logger.debug("Deleted wily cache")