code: def test_delta(self):
      es = early_stopping.EarlyStopping(min_delta=0, patience=0)
      delta_es = early_stopping.EarlyStopping(
          min_delta=1e-3, patience=0
      )
      delta_patient_es = early_stopping.EarlyStopping(
          min_delta=1e-3, patience=1
      )
      metric = 1.0
      for step in range(100):
          metric -= 1e-4
          es = es.update(metric)
          if es.should_stop:
              break
  
      self.assertEqual(step, 99)
  
      metric = 1.0
      for step in range(100):
          metric -= 1e-4
          delta_es = delta_es.update(metric)
          if delta_es.should_stop:
              break
  
      self.assertEqual(step, 1)
  
      metrics = [
          0.01,
          0.005,
          0.0033,
          0.0025,
          0.002,
          0.0017,
          0.0014,
          0.0012,
          0.0011,
          0.001,
      ]
      improvement_steps = 0
      for step in range(10):
          metric = metrics[step]
          delta_patient_es = delta_patient_es.update(metric)
          if delta_patient_es.has_improved:
              improvement_steps += 1
          if delta_patient_es.should_stop:
              break
  
      self.assertEqual(improvement_steps, 4)  # steps 0, 1, 2, 4
      self.assertEqual(step, 6)
  
imports: import jax
  from absl.testing import absltest
  from flax.training import early_stopping
label_desc: Use image node_id 3 for calling the EarlyStoppingTests obj's underlying member method code with example usage: obj.test_delta() without return types