code: def test_warning_given_when_one_query_gives_no_results(self):
      g1 = nx.MultiDiGraph()
      g1.add_node("x")
      g2 = nx.MultiDiGraph()
      g2.add_node("y")
      queries = [
          Query(g1, "match $x iid V123;"),
          Query(g2, "match $y iid V123;"),
      ]
  
      class MockTransaction:
          def query(self):
              return MockQueryManager()
  
      class MockQueryManager:
          def match(self, query):
              if query == "match $x iid V123;":
                  return [
                      MockConceptMap(
                          {
                              "x": MockThing(
                                  "V123",
                                  MockType("V4123", "person", "ENTITY"),
                              )
                          }
                      )
                  ]
              elif query == "match $y iid V123;":
                  return []
  
      mock_tx = MockTransaction()
  
      with self.assertWarns(UserWarning) as context:
          build_graph_from_queries(queries, mock_tx)
  
      self.assertEqual(
          f'There were no results for query: \n"match $y iid V123;"\nand so nothing will be added to the graph for this query',
          str(context.warning),
      )
  
imports: import unittest
  import networkx
  from typedb.api.concept.type.attribute_type import AttributeType
  from typedb_ml.networkx.graph_test_case import GraphTestCase
  from typedb_ml.networkx.queries_to_networkx import concept_dict_from_concept_map, combine_n_graphs, build_graph_from_queries
  from typedb_ml.networkx.query_graph import Query
  from typedb_ml.typedb.test.mock.answer import MockConceptMap
  from typedb_ml.typedb.test.mock.concept import MockType, MockAttributeType, MockThing, MockAttribute
  from typedb_ml.typedb.thing import Thing
label_desc: Use image node_id 2 for calling the TestBuildGraphFromQueries obj's underlying member method code with example usage: obj.test_warning_given_when_one_query_gives_no_results() and returns: MockQueryManager, list, list