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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 purge_cache(self, object_type):
 """ Purge the named cache of all values. If no cache exists for object_type, nothing is done """

        if object_type in self.mapping:
            cache = self.mapping[object_type]
            log.debug("Purging [{}] cache of {} values.".format(object_type, len(cache)))
            cache.purge()