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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(self, key):
 """ because memcached does not provide a function to check if a key is existed so here is a heck way, if the value is None, then raise Exception """

        if isinstance(key, unicode):
            key = key.encode('utf-8')
        v = self.client.get(key)
        if v is None:
            raise KeyError("Cache key [%s] not found" % key)
        else:
            return v