code: def test_predict(self):
      y_predicted = self.art_model.predict(self.x_test_diabetes[:4])
      np.testing.assert_equal(len(np.unique(y_predicted)), 4)
  
imports: from __future__ import absolute_import, division, print_function, unicode_literals
  import logging
  import unittest
  import numpy
  from art.estimators.regression.keras import KerasRegressor
  from tests.utils import TestBase, master_seed, get_tabular_regressor_kr
label_desc: Use image node_id 3 for calling the TestKerasRegressorClass obj's underlying member method code with example usage: obj.test_predict() without return types