part7b of tutorial has no result returned back

Created by: jsncepu

Hi. I have build the project sucessfully by following the tutorial part7a. However, after I copied the files to pynq boards and executed commands in part7b, I got nothing. It seems that the command: y_hw, latency, throughput = nn.predict(X_test, profile=True) never terminates. So how can I fix the problem? Could anyone give me some advices? Thanks a lot!