class_docstr: Tests variable utterance text data class.
      
docstr: Tests padding.
          
docstr_tok: ["Tests","padding","."]
code: def test_pad_to_max_length(self):
      """Tests padding."""
      hparams = copy.copy(self._hparams)
      hparams["dataset"].update(
          {
              "max_seq_length": 20,
              "length_filter_mode": "truncate",
              "pad_to_max_seq_length": True,
          }
      )
      self._run_and_test(hparams)
  
imports: import tempfile
  import copy
  import numpy
  import tensorflow
  import texar.tf
label_desc: Use image node_id 4 for calling the VarUttMonoTextDataTest obj's underlying member method code with example usage: obj.test_pad_to_max_length() without return types