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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 ensure_exists(self):
 """Ensure that cache directory exists."""

        if not cache.exists(self.config):
            logger.debug("Wily cache not found, creating.")
            cache.create(self.config)
            logger.debug("Created wily cache")
        else:
            logger.debug(f"Cache {self.config.cache_path} exists")