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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 expire_leaderboard_at_for(self, leaderboard_name, timestamp):
        '''
        Expire the given leaderboard at a specific UNIX timestamp. Do not use this with
        leaderboards that utilize member data as there is no facility to cascade the
        expiration out to the keys for the member data.

        @param leaderboard_name [String] Name of the leaderboard.
        @param timestamp [int] UNIX timestamp at which the leaderboard will be expired.
        '''
        pipeline = self.redis_connection.pipeline()
        pipeline.expireat(leaderboard_name, timestamp)
        pipeline.expireat(
            self._ties_leaderboard_key(leaderboard_name), timestamp)
        pipeline.expireat(self._member_data_key(leaderboard_name), timestamp)
        pipeline.execute()