In the sample seq2seq code given by fchollet, how can I add more LSTM layers to the encoder and decoder? I'm having some trouble with the shapes and a bit confused in general. Thanks.
Keras' functional api lets you call layers. This lets you chain another layer on top the output of an existing layer by calling it. For example here:
encoder_inputs = Input(shape=(None, num_encoder_tokens))
encoder = LSTM(latent_dim, return_sequences=True)
encoder_outputs, state_h, state_c = LSTM(latent_dim, return_state=True)(encoder(encoder_inputs))