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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 current_batch(self):
 """Return the batch id for the tag. :return: :class: `int` current batch id """

        current_batch = memcache.get(self.group_key)

        if not current_batch:
            memcache.add(self.group_key, 1)
            current_batch = 1

        return current_batch