code: def test_actor_picking(sphere):
      picked = []
  
      def callback(picked_actor):
          picked.append(picked_actor)
  
      pl = pv.Plotter()
      actor = pl.add_mesh(sphere)
      pl.enable_mesh_picking(callback=callback, use_actor=True)
      pl.show(auto_close=False)
  
      width, height = pl.window_size
  
      pl.iren._mouse_right_button_click(width // 2, height // 2)
  
      assert actor in picked
      assert pl.picked_mesh == sphere
  
      # invalid selection
      pl.iren._mouse_right_button_click(0, 0)
  
      assert pl.picked_mesh is None
  
imports: import os
  import numpy
  import pytest
  import vtk
  import pyvista
  from pyvista.plotting.errors import PyVistaPickingError
label_desc: Use image node_id 4 for calling a global function with example usage: test_actor_picking(sphere) without return types