code: def test_acquisition_function(self):
      self.mock_model.predict.return_value = (1, 3)
  
      weighted_acquisition = self.lcb_acquisition.acquisition_function(
          np.array([2, 2])
      )
      expected_acquisition = np.array([[-5.0], [-5.0]])
  
      self.assertTrue(
          np.array_equal(expected_acquisition, weighted_acquisition)
      )
  
file_path: GPyOpt/GPyOpt/testing/acquisitions_tests/test_lcb_acquisition.py
imports: import unittest
  from mock import Mock
  import numpy
  from GPyOpt.acquisitions import AcquisitionLCB
  from GPyOpt.core.task.space import Design_space
label_desc: Use image node_id 2 for calling the TestLCBAcquisition obj's underlying member method code with example usage: obj.test_acquisition_function() without return types