code: def constant(step, total_train_steps, value=1.0):
      """Constant learning rate (multiplier).
  
      Args:
        step: a tf.Scalar
        total_train_steps: a number
        value: a number or tf.Scalar
  
      Returns:
        a tf.Scalar, the learning rate for the step.
      """
      del step, total_train_steps
      return value
  
file_path: mesh/mesh_tensorflow/transformer/learning_rate_schedules.py
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import math
  import gin
  import tensorflow.compat.v1
label_desc: Use image node_id 5 for calling a global function with example usage: constant(step, total_train_steps, value) and returns: value