code: def test_epoch_metrics(self):
      actual = rename_doubles([], ["a", "a"])
      expected = [], ["a1", "a2"]
      self.assertEqual(expected, actual)
  
      actual = rename_doubles([], ["a", "b", "a", "a", "c", "d"])
      expected = [], ["a1", "b", "a2", "a3", "c", "d"]
      self.assertEqual(expected, actual)
  
imports: import os
  import unittest
  from unittest import skipIf
  from unittest.mock import ANY
  import numpy
  import torch
  import torch.nn
  import torchmetrics
  from poutyne import Metric, Model, do_register_metric_class, rename_doubles, unregister_metric_class
label_desc: Use image node_id 2 for calling the MetricsRenamingTest obj's underlying member method code with example usage: obj.test_epoch_metrics() without return types