code: def _softplus_inverse(x):
      """Helper which computes the function inverse of `tf.nn.softplus`."""
      return tf.log(tf.math.expm1(x))
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import collections
  from magenta.models.image_stylization import ops
  from tensor2tensor.layers import common_hparams
  from tensor2tensor.layers import common_layers
  from tensor2tensor.utils import registry
  from tensor2tensor.utils import t2t_model
  import tensorflow.compat.v1
  from tensorflow.compat.v1 import estimator
  import tensorflow_probability
label_desc: Use image node_id 1 for calling a global function with example usage: _softplus_inverse(x) and returns: tf