class_docstr: Tests text data class.
      
docstr: Tests discard lenghy seq.
          
docstr_tok: ["Tests","discard","lenghy","seq","."]
code: def test_length_discard(self):
      """Tests discard lenghy seq."""
      hparams = copy.copy(self._hparams)
      hparams["dataset"].update(
          {"max_seq_length": 4, "length_filter_mode": "discard"}
      )
      self._run_and_test(hparams)
  
imports: import tempfile
  import copy
  import numpy
  import tensorflow
  import texar.tf
label_desc: Use image node_id 10 for calling the MonoTextDataTest obj's underlying member method code with example usage: obj.test_length_discard() without return types