code: def test_volume(test_images, tmp_path):
      fname1 = test_images / "stent.npz"
      vol1 = iio.volread(fname1)
      assert vol1.shape == (256, 128, 128)
  
      fname = tmp_path / "stent.bsdf"
      iio.volsave(fname, vol1)
  
      vol2 = iio.volread(fname)
      assert vol1.shape == vol2.shape
      assert np.all(vol1 == vol2)
  
file_path: imageio/tests/test_bsdf.py
imports: import numpy
  from pytest import raises
  from imageio import core
  import imageio.v2
  from imageio.plugins import _bsdf
  import pytest
  import sys
  from conftest import deprecated_test
label_desc: Use image node_id 7 for calling a global function with example usage: test_volume(test_images, tmp_path) without return types