code: def test_incorrect_centers(self):
      self.assertRaises(ValueError, kmedians, [[0], [1], [2]], [])
  
imports: import unittest
  import numpy
  import matplotlib
  from pyclustering.cluster.tests.kmedians_templates import KmediansTestTemplates
  from pyclustering.cluster.kmedians import kmedians
  from pyclustering.samples.definitions import SIMPLE_SAMPLES
  from pyclustering.utils import read_sample
  from pyclustering.utils.metric import type_metric, distance_metric
label_desc: Use image node_id 42 for calling the KmediansUnitTest obj's underlying member method code with example usage: obj.test_incorrect_centers() without return types