code: def _wrap_activity_regularizer(layer):
      """Wraps the activity regularizer."""
      # pylint: disable=protected-access
      if isinstance(layer._activity_regularizer, def_function.Function):
          return layer._activity_regularizer
      return def_function.Function(
          layer._activity_regularizer,
          "{}_activity_regularizer".format(layer.name),
          input_signature=[
              tensor_spec.TensorSpec(
                  None, layer._compute_dtype or K.floatx()
              )
          ],
      )
  
imports: import functools
  import threading
  import weakref
  from tensorflow.python.eager import def_function
  from tensorflow.python.framework import tensor_shape
  from tensorflow.python.framework import tensor_spec
  from tensorflow.python.keras import backend
  from tensorflow.python.keras.engine import base_layer_utils
  from tensorflow.python.keras.engine import input_spec
  from tensorflow.python.keras.mixed_precision import autocast_variable
  from tensorflow.python.keras.saving import saving_utils
  from tensorflow.python.keras.saving.saved_model import constants
  from tensorflow.python.keras.saving.saved_model import load
  from tensorflow.python.keras.saving.saved_model import serialized_attributes
  from tensorflow.python.keras.saving.saved_model import utils
  from tensorflow.python.keras.utils import tf_contextlib
  from tensorflow.python.keras.utils import tf_inspect
  from tensorflow.python.keras.utils import tf_utils
  from tensorflow.python.keras.utils import version_utils
  from tensorflow.python.keras.utils.generic_utils import LazyLoader
  from tensorflow.python.platform import tf_logging
  from tensorflow.python.trackable import data_structures
  from tensorflow.python.util import nest
  from tensorflow.python.util import tf_decorator
label_desc: Use image node_id 19 for calling a global function with example usage: _wrap_activity_regularizer(layer) and returns: def_function, layer