code: def test_validation_on(self) -> None:
      assert bcpb.Property._should_validate is True
      assert bcpb.validation_on()
  
      bcpb.Property._should_validate = False
      assert not bcpb.validation_on()
  
      bcpb.Property._should_validate = True
      assert bcpb.validation_on()
  
imports: from __future__ import annotations
  import pytest
  from typing import Any
  from unittest.mock import MagicMock, patch
  import numpy
  import pandas
  from bokeh.core.has_props import HasProps
  from tests.support.util.api import verify_all
  from tests.support.util.types import Capture
  import bokeh.core.property.bases
label_desc: Use image node_id 13 for calling the TestProperty obj's underlying member method code with example usage: obj.test_validation_on() without return types