code: def constant_learning_rate(
      step, total_train_steps, learning_rate=gin.REQUIRED
  ):
      """Learning rate independent of step.
  
      DEPRECATED: use constant() or pass a float directly to utils.run.learning_rate
  
      Args:
        step: a tf.Scalar
        total_train_steps: a number
        learning_rate: a number or tf.Scalar
  
      Returns:
        a tf.Scalar, the learning rate for the step.
      """
      del step, total_train_steps
      return tf.cast(learning_rate, tf.float32)
  
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 6 for calling a global function with example usage: constant_learning_rate(step, total_train_steps, learning_rate) and returns: tf