code: def test_stateless_result(self):
      metric = ExampleMetric(name="mse")
      res = metric.stateless_result(
          [ops.ones(()) * 12, ops.ones(()) * 3]
      )
      self.assertAllClose(res, 4.0)
  
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 3 for calling the MetricTest obj's underlying member method code with example usage: obj.test_stateless_result() without return types