code: def test_metric_observation_repr():
      assert (
          repr(metrics_tracking.MetricObservation(0.5, step=0))
          == "MetricObservation(value=[0.5], step=0)"
      )
  
imports: import random
  import numpy
  import pytest
  from keras_tuner.backend.keras import losses
  from keras_tuner.backend.keras import metrics
  from keras_tuner.engine import metrics_tracking
label_desc: Use image node_id 5 for calling a global function with example usage: test_metric_observation_repr() without return types