用keras（TensorFlow后端）跑LSMT的时候出现了下面的问题。
Traceback (most recent call last):
File "/Users/zhaojing/PycharmProjects/CWS_02/lstm01.py", line 94, in
model.fit(np.array(list(d['x'])).reshape(-1,maxlen), np.array(list(d['y'])).reshape((-1,maxlen,5)), batch_size=batch_size, epochs=1)
File "/usr/local/lib/python3.6/site-packages/keras/engine/training.py", line 1705, in fit
validation_steps=validation_steps)
File "/usr/local/lib/python3.6/site-packages/keras/engine/training.py", line 1256, in _fit_loop
callbacks.on_epoch_end(epoch, epoch_logs)
File "/usr/local/lib/python3.6/site-packages/keras/callbacks.py", line 77, in on_epoch_end
callback.on_epoch_end(epoch, logs)
File "/usr/local/lib/python3.6/site-packages/keras/callbacks.py", line 339, in on_epoch_end
self.progbar.update(self.seen, self.log_values)
AttributeError: 'ProgbarLogger' object has no attribute 'log_values'
请问这个问题该怎么解决呢。
keras 版本：2.1.6 和TensorFlow 版本1.8.0rc1
