The layer “concatenate” 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.
This error pops when trying to print the summary of the model.
def modelf(Tx, Ty, n_a, n_s, human_vocab_size, machine_vocab_size):
# mentor edit: code removed
return model