code: def test_gauc(self):
      name = "gauc"
      self.assertEqual(
          get_metric_result(name, case=0),
          (
              1 * ((2 - (1 - 1) / 2 - 1 / 1) / (2 - 1))
              + 2 * ((3 - (2 - 1) / 2 - 4 / 2) / (3 - 2))
              + 3 * ((5 - (3 - 1) / 2 - 9 / 3) / (5 - 3))
          )
          / (1 + 2 + 3),
      )
      self.assertEqual(
          get_metric_result(name, case=1), (3 - 0 - 3 / 1) / (3 - 1)
      )
  
file_path: RecBole/tests/metrics/test_rank_metrics.py
imports: import os
  import sys
  import unittest
  import numpy
  from recbole.config import Config
  from recbole.evaluator import metrics_dict, Collector
label_desc: Use image node_id 1 for calling the TestRankMetrics obj's underlying member method code with example usage: obj.test_gauc() without return types