code: def test_config(self):
      mean_obj = reduction_metrics.Mean(name="mean", dtype="float32")
      self.assertEqual(mean_obj.name, "mean")
      self.assertEqual(len(mean_obj.variables), 2)
      self.assertEqual(mean_obj._dtype, "float32")
  
      # Check save and restore config
      mean_obj2 = reduction_metrics.Mean.from_config(
          mean_obj.get_config()
      )
      self.assertEqual(mean_obj2.name, "mean")
      self.assertEqual(len(mean_obj2.variables), 2)
      self.assertEqual(mean_obj2._dtype, "float32")
  
imports: import numpy
  from keras import testing
  from keras.metrics import reduction_metrics
  from keras.saving import register_keras_serializable
label_desc: Use image node_id 1 for calling the MeanTest obj's underlying member method code with example usage: obj.test_config() without return types