code: def test_nn_errors_on_multiclass():
      """Assert that TPOT-NN throws an error when you try to pass training data with > 2 classes. (NN)"""
      clf = TPOTClassifier(
          random_state=42,
          population_size=1,
          generations=1,
          config_dict=classifier_config_nn,
          template="PytorchLRClassifier",
      )
      assert_raises(ValueError, clf.fit, multiclass_X, multiclass_y)
  
file_path: tpot/tests/nn_tests.py
imports: from tpot import TPOTClassifier
  from tpot.config import classifier_config_nn
  from tpot.builtins import nn
  import numpy
  import pandas
  from sklearn.datasets import make_classification
  from sklearn.model_selection import train_test_split
  from nose.tools import nottest, assert_raises
  from itertools import repeat
label_desc: Use image node_id 2 for calling a global function with example usage: test_nn_errors_on_multiclass() without return types