hello I think I wrote everything correctly but I got this error in Ex2, Neural Machine Translation:
AttributeError: The layer “concatenate_1” has multiple inbound nodes, with different output shapes. Hence the notion of “output shape” is ill-defined for the layer. Use get_output_shape_at(node_index) instead.
I fixed this in my case by applying the troubleshooting note from the Notebook:
If you are getting repeated errors after an initially incorrect implementation of “model”, but believe that you have corrected the error, you may still see error messages when building your model.
A solution is to save and restart your kernel (or shutdown then restart your notebook), and re-run the cells.
In my case I had previously setup the Bi-LSTM to have Tx units, rather than n_a units.