code: def test_incorrect_data(self):
      self.assertRaises(ValueError, bang, [], 1)
  
imports: import unittest
  import matplotlib
  from pyclustering.cluster.tests.bang_templates import bang_test_template
  from pyclustering.cluster.bang import bang
  from pyclustering.samples.definitions import SIMPLE_SAMPLES
label_desc: Use image node_id 24 for calling the bang_unit_test obj's underlying member method code with example usage: obj.test_incorrect_data() without return types