code: def test_has_number_of_classes():
      param = HasNumberOfClasses()
      assert param.get_nb_classes() == 10
      classes = 42
      param.set_nb_classes(classes)
      assert param.get_nb_classes() == classes
  
file_path: elephas/tests/ml/test_params.py
imports: from elephas.ml.params import *
label_desc: Use image node_id 5 for calling a global function with example usage: test_has_number_of_classes() without return types