code: def test_add_new_trial(self):
      lineages = Lineages()
      assert len(lineages) == 0
      lineage = lineages.add(TrialStub(id="stub"))
      assert len(lineages) == 1
      assert lineages._lineage_roots[0] is lineage
      assert lineages._trial_to_lineages["stub"] is lineage
  
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 1 for calling the TestLineages obj's underlying member method code with example usage: obj.test_add_new_trial() without return types