(ubuntu) Please help model.save error in keras

model.fit(TrainX, TrainY, batch_size=30, epochs=3, verbose=1)

model.save("models.h5")

File "/usr/local/lib/python3.7/site-packages/h5py/_hl/group.py", line 143, in create_dataset 
 if '/' in name:
TypeError: a bytes-like object is required, not 'str'