code: def StopGradient():
      """Returns an identity layer with a stop gradient."""
      return Fn("StopGradient", lambda x: fastmath.stop_gradient(x))
  
imports: from absl import logging
  import numpy
  import tensorflow
  from trax import fastmath
  from trax.fastmath import numpy
  from trax.layers import base
  from trax.layers import initializers
  from trax.layers.assert_shape import assert_shape
  from trax.layers.base import Fn
label_desc: Use image node_id 14 for calling a global function with example usage: StopGradient() and returns: Fn