code: def test_empty_methods(self):
      metric = AdvancedMetric("test")
  
      self.assertTrue(metric.process_train() is None)
      self.assertTrue(metric.process_final_train() is None)
      self.assertTrue(metric.process_validate() is None)
      self.assertTrue(metric.process_final_validate() is None)
  
imports: import unittest
  from mock import Mock
  from torchbearer.metrics import MetricList, Metric, MetricTree, AdvancedMetric
label_desc: Use image node_id 1 for calling the TestAdvancedMetric obj's underlying member method code with example usage: obj.test_empty_methods() without return types