code: def _metric_display_name(self, metric):
      metric_display_names = {
          "accuracy": "Accuracy",
          "auc": "Area Under Curve",
          "log_loss": "Log Loss",
          "max_error": "Max Error",
          "rmse": "Root-Mean-Square Error",
      }
      if metric in metric_display_names:
          return metric_display_names[metric]
      else:
          return metric
  
imports: from __future__ import print_function
  from __future__ import division
  from __future__ import absolute_import
  import unittest
  import turicreate
  from turicreate.toolkits._main import ToolkitError
  import random
label_desc: Use image node_id 2 for calling the TreeRegressionTrackingMetricsTest obj's underlying member method code with example usage: obj._metric_display_name(metric) and returns: metric_display_names, metric