code: def test_reset(self):
      root = Metric("test")
      root.reset = Mock()
      leaf = Metric("test")
      leaf.reset = Mock()
  
      tree = MetricTree(root)
      tree.add_child(leaf)
  
      tree.reset({})
      root.reset.assert_called_once_with({})
      leaf.reset.assert_called_once_with({})
  
imports: import unittest
  from mock import Mock
  from torchbearer.metrics import MetricList, Metric, MetricTree, AdvancedMetric
label_desc: Use image node_id 6 for calling the TestMetricTree obj's underlying member method code with example usage: obj.test_reset() without return types