code: def test_logo_voxel():
      grid = demos.logo_voxel()
      assert grid.n_cells
  
file_path: pyvista/tests/plotting/test_demos.py
imports: import os
  import platform
  import numpy
  import pytest
  import pyvista
  from pyvista import demos
  from pyvista.plotting import system_supports_plotting
label_desc: Use image node_id 4 for calling a global function with example usage: test_logo_voxel() without return types