ValueError????????????????????????????????Traceback?(most?recent?call?last)<ipython-input-34-5f15418b3570>?in?<module>---->?1?model.summary()C:\Anaconda3\lib\site-packages\keras\engine\network.py?in?summary(self,?line_length,?positions,?print_fn)???1250?????????if?not?self.built:???1251?????????????raise?ValueError(->?1252?????????????????'This?model?has?not?yet?been?built.?'???1253?????????????????'Build?the?model?first?by?calling?build()?'???1254?????????????????'or?calling?fit()?with?some?data.?'ValueError:?This?model?has?not?yet?been?built.?Build?the?model?first?by?calling?build()?or?calling?fit()?with?some?data.?Or?specify?input_shape?or?batch_input_shape?in?the?first?layer?for?automatic?build.