code: def testExceptions(self):
      with self.assertRaises(ValueError):
          reservoir.Reservoir(-1)
      with self.assertRaises(ValueError):
          reservoir.Reservoir(13.3)
  
      r = reservoir.Reservoir(12)
      with self.assertRaises(KeyError):
          r.Items("missing key")
  
imports: import tensorflow
  from tensorboard.backend.event_processing import reservoir
label_desc: Use image node_id 4 for calling the ReservoirTest obj's underlying member method code with example usage: obj.testExceptions() without return types