class_docstr: Tests learning rate decay function.
    
class_docstr_tok: ["Tests","learning","rate","decay","function","."]
code: def test_no_decay(self):
      decay_fn = training_utils.create_learning_rate_decay_fn(
          decay_type=None, decay_steps=5, decay_rate=2.0
      )
      self.assertEqual(decay_fn, None)
  
      decay_fn = training_utils.create_learning_rate_decay_fn(
          decay_type="", decay_steps=5, decay_rate=2.0
      )
      self.assertEqual(decay_fn, None)
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  from __future__ import unicode_literals
  import tempfile
  import tensorflow
  import numpy
  from seq2seq.contrib import rnn_cell
  from seq2seq.data import input_pipeline
  from seq2seq.test import utils
  from seq2seq.training import utils
label_desc: Use image node_id 1 for calling the TestLRDecay obj's underlying member method code with example usage: obj.test_no_decay() without return types