code: def test_identify_backdoor_unobserved_not_in_backdoor_set(
      self, example_graph_solution: IdentificationTestGraphSolution
  ):
      graph = example_graph_solution.graph
      observed_variables = example_graph_solution.observed_nodes
      identifier = AutoIdentifier(
          estimand_type=EstimandType.NONPARAMETRIC_ATE,
          backdoor_adjustment=BackdoorAdjustment.BACKDOOR_EXHAUSTIVE,
      )
  
      backdoor_results = identifier.identify_backdoor(
          graph,
          observed_nodes=example_graph_solution.observed_nodes,
          action_nodes=["X"],
          outcome_nodes=["Y"],
          include_unobserved=False,
      )
      backdoor_sets = [
          set(backdoor_result_dict["backdoor_set"])
          for backdoor_result_dict in backdoor_results
          if len(backdoor_result_dict["backdoor_set"]) > 0
      ]
  
      assert all(
          [
              variable in observed_variables
              for backdoor_set in backdoor_sets
              for variable in backdoor_set
          ]
      )
  
file_path: dowhy/tests/causal_identifiers/test_backdoor_identifier.py
imports: import pytest
  from dowhy.causal_identifier import AutoIdentifier, BackdoorAdjustment
  from dowhy.causal_identifier.identify_effect import EstimandType
  from .base import IdentificationTestGraphSolution, example_graph_solution
label_desc: Use image node_id 2 for calling the TestBackdoorIdentification obj's underlying member method code with example usage: obj.test_identify_backdoor_unobserved_not_in_backdoor_set(example_graph_solution) without return types