code: def testPruneMiscObject(self):
      model = object()
      with self.assertRaises(ValueError) as e:
          _ = prune.prune_low_magnitude(model, **self.params)
      self.assertEqual(
          str(e.exception),
          self.INVALID_TO_PRUNE_PARAM_ERROR.format(input="object"),
      )
  
imports: import json
  import tempfile
  import numpy
  import tensorflow
  from tensorflow_model_optimization.python.core.keras import test_utils
  from tensorflow_model_optimization.python.core.sparsity.keras import prunable_layer
  from tensorflow_model_optimization.python.core.sparsity.keras import prune
  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 23 for calling the PruneTest obj's underlying member method code with example usage: obj.testPruneMiscObject() without return types