def METHOD_NAME(self):
    seq0 = '12-blahblah'
    self.pillow.set_checkpoint({'seq': seq0})
    HistoricalPillowCheckpoint.create_checkpoint_snapshot(self.pillow.checkpoint)
    seq1 = '10-blahblah'
    self.pillow.set_checkpoint({'seq': seq1})
    HistoricalPillowCheckpoint.create_checkpoint_snapshot(self.pillow.checkpoint)
    seq2 = '2-blahblah'
    self.pillow.set_checkpoint({'seq': seq2})
    HistoricalPillowCheckpoint.create_checkpoint_snapshot(self.pillow.checkpoint)
    store = HistoricalPillowCheckpoint.get_historical_max(self.pillow.checkpoint.checkpoint_id)
    self.assertIsNotNone(store)
    self.assertEqual(store.seq, seq0)
    store = HistoricalPillowCheckpoint.get_historical_max('CheckpointThatDoesNotExist')
    self.assertIsNone(store)