code: def collect_prunable_layers(model):
      """Recursively collect the prunable layers in the model."""
      prunable_layers = []
      for layer in model.layers:
          # A keras model may have other models as layers.
          if isinstance(layer, tf.keras.Model):
              prunable_layers += collect_prunable_layers(layer)
          if isinstance(layer, PruneLowMagnitude):
              prunable_layers.append(layer)
  
      return prunable_layers
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import inspect
  import re
  import numpy
  import tensorflow
  from tensorflow_model_optimization.python.core.keras import compat
  from tensorflow_model_optimization.python.core.keras import metrics
  from tensorflow_model_optimization.python.core.keras import utils
  from tensorflow_model_optimization.python.core.sparsity.keras import prunable_layer
  from tensorflow_model_optimization.python.core.sparsity.keras import prune_registry
  from tensorflow_model_optimization.python.core.sparsity.keras import pruning_impl
  from tensorflow_model_optimization.python.core.sparsity.keras import pruning_schedule
  from tensorflow_model_optimization.python.core.sparsity.keras.pruning_utils import convert_to_tuple_of_two_int
label_desc: Use image node_id 2 for calling a global function with example usage: collect_prunable_layers(model) and returns: prunable_layers