'Test that repeated normalizations do not change the kernel [#3747].'

def test_kernel_normalization(self):

    kernel = CustomKernel(np.ones(5))
    kernel.normalize()
    data = np.copy(kernel.array)
    kernel.normalize()
    assert_allclose(data, kernel.array)
    kernel.normalize()
    assert_allclose(data, kernel.array)
