code: def __init__(self, name="mean_square_error", dtype=None):
      super().__init__(name=name, dtype=dtype)
      self.sum = self.add_variable(
          name="sum", shape=(), initializer=initializers.Zeros()
      )
      self.total = self.add_variable(
          name="total",
          shape=(),
          initializer=initializers.Zeros(),
          dtype="int32",
      )
  
imports: import numpy
  from keras import backend
  from keras import initializers
  from keras import metrics
  from keras import ops
  from keras import testing
  from keras.metrics.metric import Metric
label_desc: Use image node_id 1 to create a new ExampleMetric object from inherited base classes: Metric with example: obj = ExampleMetric(name, dtype)