def test_2D_array2(self):
     a = np.array([1, 2])
     b = np.array([1, 2])
     res = dstack([a, b])
     desired = np.array([[[1, 1], [2, 2]]])
     assert_array_equal(res, desired)

 def test_generator(self):
     with assert_warns(FutureWarning):
         dstack((np.arange(3) for _ in range(2)))

 def test_0D_array(self):
     a = np.array(1)
     b = np.array(2)
     res = dstack([a, b])
     desired = np.array([[[1, 2]]])
     assert_array_equal(res, desired)

def getBlackWhiteFromBinary(img):
    return dstack((img,img,img))