code: def test_vol_actor_prop(vol_actor):
      assert isinstance(vol_actor.prop, vtk.vtkVolumeProperty)
  
      prop = vtk.vtkVolumeProperty()
      vol_actor.prop = prop
      assert vol_actor.prop is prop
  
imports: import platform
  import numpy
  import pytest
  import vtk
  import pyvista
  from pyvista import examples
label_desc: Use image node_id 22 for calling a global function with example usage: test_vol_actor_prop(vol_actor) without return types