code: def testCustomLayerNonPrunable(self):
      layer = CustomLayer(input_dim=16, output_dim=32)
      inputs = keras.layers.Input(shape=(16))
      _ = layer(inputs)
      with self.assertRaises(ValueError):
          pruning_wrapper.PruneLowMagnitude(
              layer, block_pooling_type="MAX"
          )
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import tensorflow
  from tensorflow_model_optimization.python.core.sparsity.keras import pruning_schedule
  from tensorflow_model_optimization.python.core.sparsity.keras import pruning_wrapper
label_desc: Use image node_id 8 for calling the PruningWrapperTest obj's underlying member method code with example usage: obj.testCustomLayerNonPrunable() without return types