BPE = 40000
2020-02-16 15:44:07,041  dev bleu:  46.15 [Beam search decoding with beam size = 5 and alpha = 1.0]
2020-02-16 15:44:51,075 test bleu:  41.23 [Beam search decoding with beam size = 5 and alpha = 1.0]