code: def test_rmse(self):
      name = "rmse"
      self.assertEqual(
          get_result(name, case=0),
          np.sqrt((0.9**2 + 0.9**2 + 0.8**2 + 0.7**2) / 4),
      )
      self.assertEqual(
          get_result(name, case=1),
          np.sqrt((0.7**2 + 0.5**2 + 0.4**2 + 0.2**2) / 4),
      )
  
file_path: RecBole/tests/metrics/test_loss_metrics.py
imports: import os
  import sys
  import unittest
  import numpy
  from recbole.config import Config
  from recbole.evaluator.register import metrics_dict
label_desc: Use image node_id 2 for calling the TestLossMetrics obj's underlying member method code with example usage: obj.test_rmse() without return types