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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 regenerate(self):
 """Regenerate the session id. This function creates a new session id and stores all information associated with the current id in that new id. It then destroys the old session id. This is useful for preventing session fixation attacks and should be done whenever someone uses a login to obtain additional authorizaiton. """


        oldhash = self.session_hash
        self.new_session_id()
        try:
            self.rdb.rename(oldhash,self.session_hash)
            self.rdb.expire(self.session_hash,self.ttl)
        except:
            pass