code: def test_actor_init_empty():
      actor = pv.Actor()
      assert "Position" in repr(actor)
      assert "Has mapper" in repr(actor)
      assert "Mapper" not in repr(actor)
      assert isinstance(actor.prop, pv.Property)
      assert actor.mapper is None
  
      with pytest.raises(AttributeError):
          actor.not_an_attribute = None
  
      assert actor.memory_address == actor.GetAddressAsString("")
  
imports: import platform
  import numpy
  import pytest
  import vtk
  import pyvista
  from pyvista import examples
label_desc: Use image node_id 4 for calling a global function with example usage: test_actor_init_empty() without return types