code: def test_incorrect_kmax(self):
      self.assertRaises(ValueError, elbow, [[0], [1], [2]], 1, 10)
  
imports: import unittest
  import matplotlib
  from pyclustering.cluster.center_initializer import random_center_initializer
  from pyclustering.cluster.elbow import elbow
  from pyclustering.cluster.tests.elbow_template import elbow_test_template
  from pyclustering.samples.definitions import SIMPLE_SAMPLES, SIMPLE_ANSWERS
label_desc: Use image node_id 31 for calling the elbow_unit_test obj's underlying member method code with example usage: obj.test_incorrect_kmax() without return types