code: def test_mae(self):
      predicted = asfloat(np.array([1, 2, 3]))
      target = asfloat(np.array([3, 2, 1]))
  
      actual = objectives.mae(target, predicted)
      self.assertAlmostEqual(self.eval(actual), 4 / 3.0, places=3)
  
file_path: neupy/tests/algorithms/gd/test_objectives.py
imports: import numpy
  from neupy.utils import asfloat
  from neupy.algorithms.gd import objectives
  from base import BaseTestCase
label_desc: Use image node_id 6 for calling the ErrorFuncTestCase obj's underlying member method code with example usage: obj.test_mae() without return types