code: def test_empty_labels():
      image = np.random.random((5, 5))
      labels = np.zeros((5, 5), dtype=int)
  
      with testing.raises(ValueError, match="No seeds provided"):
          random_walker(image, labels)
  
      labels[1, 1] = -1
      with testing.raises(ValueError, match="No seeds provided"):
          random_walker(image, labels)
  
      # Once seeds are provided, it should run without error
      labels[3, 3] = 1
      random_walker(image, labels)
  
imports: import numpy
  from skimage._shared import testing
  from skimage._shared._warnings import expected_warnings
  from skimage._shared.testing import xfail, arch32
  from skimage.segmentation import random_walker
  from skimage.transform import resize
label_desc: Use image node_id 24 for calling a global function with example usage: test_empty_labels() without return types