code: def test_get_best_trial_non_completed_root(self):
      lineage = LineageNode(TrialStub(id="my-id"))
      assert lineage.get_best_trial() is None
  
imports: import os
  import random
  import pytest
  from base import ObjectiveStub, TrialStub, build_full_tree, build_population, compare_generations
  from orion.algo.pbt.pbt import LineageNode, Lineages
label_desc: Use image node_id 14 for calling the TestLineageNode obj's underlying member method code with example usage: obj.test_get_best_trial_non_completed_root() without return types