code: def test_no_validity_dims(
      consistent_id_object_repository: ConsistentIdObjectRepository,
      scd_semantic_manifest_lookup: SemanticManifestLookup,
  ) -> None:
      """Tests converting an instance set with no matching dimensions to a ValidityWindowJoinDescription."""
      # bookings_source is a fact table, and has no validity window dimensions
      dataset = consistent_id_object_repository.scd_model_data_sets[
          "bookings_source"
      ]
  
      validity_window_join_description = CreateValidityWindowJoinDescription(
          semantic_model_lookup=scd_semantic_manifest_lookup.semantic_model_lookup
      ).transform(
          instance_set=dataset.instance_set
      )
  
      assert validity_window_join_description is None, (
          f"We managed to create a validity window join description `{validity_window_join_description}` from a "
          f"semantic model that does not have one defined!"
      )
  
file_path: metricflow/metricflow/test/plan_conversion/instance_converters/test_create_validity_window_join_description.py
imports: from __future__ import annotations
  import pytest
  from dbt_semantic_interfaces.type_enums.time_granularity import TimeGranularity
  from metricflow.dataflow.dataflow_plan import ValidityWindowJoinDescription
  from metricflow.instances import InstanceSet
  from metricflow.model.semantic_manifest_lookup import SemanticManifestLookup
  from metricflow.plan_conversion.instance_converters import CreateValidityWindowJoinDescription
  from metricflow.specs.specs import TimeDimensionSpec
  from metricflow.test.fixtures.model_fixtures import ConsistentIdObjectRepository
label_desc: Use image node_id 1 for calling a global function with example usage: test_no_validity_dims(consistent_id_object_repository, scd_semantic_manifest_lookup) without return types