code: def test_default_acc(self):
      metric = MetricList(["acc"])
      self.assertTrue(
          metric.metric_list[0].name == "acc",
          msg="acc not in: " + str(metric.metric_list),
      )
  
imports: import unittest
  from mock import Mock
  from torchbearer.metrics import MetricList, Metric, MetricTree, AdvancedMetric
label_desc: Use image node_id 2 for calling the TestMetricList obj's underlying member method code with example usage: obj.test_default_acc() without return types