def test_unsupported_op_early_error_out():
        '''
        We should error out at the point when Builder tries to add an op which is only supported in a newer spec version
        '''
        expected_err_str = (
            "No available version for pixel_unshuffle in the coremltools.target.iOS15 opset. "
            "Please update the minimum_deployment_target to at least coremltools.target.iOS16"
        )
        with pytest.raises(ValueError, match=expected_err_str):
            @mb.program(input_specs=[mb.TensorSpec(shape=(1, 1, 4, 4))], opset_version=ct.target.iOS15)
            def prog(x):
                x = mb.pixel_unshuffle(x=x, downscale_factor=np.uint32(2))
                return x

        We should error out at the point when Builder tries to add an op which is only supported in a newer spec version
        
coremltools/converters/mil/mil/tests/test_programs.py