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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _build_session_metric_values(self, session_name):
 """Builds the session metric values."""


    # result is a list of api_pb2.MetricValue instances.
    result = []
    metric_infos = self._experiment.metric_infos
    for metric_info in metric_infos:
      metric_name = metric_info.name
      try:
        metric_eval = metrics.last_metric_eval(
            self._context.multiplexer,
            session_name,
            metric_name)
      except KeyError:
        # It's ok if we don't find the metric in the session.
        # We skip it here. For filtering and sorting purposes its value is None.
        continue

      # metric_eval is a 3-tuple of the form [wall_time, step, value]
      result.append(api_pb2.MetricValue(name=metric_name,
                                        wall_time_secs=metric_eval[0],
                                        training_step=metric_eval[1],
                                        value=metric_eval[2]))
    return result