The shape of input into LSTM is (seq_len, batch, inputsize). And in the course of deep learning, I was told that step t will utilize the information from step t - 1. But after read both the Python and C++ source code, I didn’t find the iteration on ‘time’(i.e. the step on seq_len). And it seemed that all the time step of input features are calculated in parallel. So how exactly the information is pass from time step t to step t - 1?  And what is the difference between nn.LSTM and nn.LSTMCell? Does nn.LSTM is just a multi-layer version of nn.LSTMCell?
I’m so confused