class_docstr: Tests the bleu functions.
      
class_docstr_tok: ["Tests","the","bleu","functions","."]
code: def _test_sentence_bleu(
      self, references, hypothesis, lowercase, true_bleu
  ):
      bleu = sentence_bleu_moses(
          references=references,
          hypothesis=hypothesis,
          lowercase=lowercase,
      )
      self.assertAlmostEqual(bleu, true_bleu, places=2)
  
      bleu = sentence_bleu(
          references=references,
          hypothesis=hypothesis,
          lowercase=lowercase,
      )
      self.assertAlmostEqual(bleu, true_bleu, places=0)
  
file_path: texar/tests/evals/bleu_test.py
imports: import numpy
  import tensorflow
  from texar.tf.evals.bleu_moses import sentence_bleu_moses, corpus_bleu_moses
  from texar.tf.evals.bleu import sentence_bleu, corpus_bleu
label_desc: Use image node_id 1 for calling the BLEUTest obj's underlying member method code with example usage: obj._test_sentence_bleu(references, hypothesis, lowercase, true_bleu) without return types