I just need to find out how to put that last context vector into the initial state of Decorder.
Example::

n_vocab = 3160
n_embed = 16
hidden_size = 16
model = Encorder(n_vocab,n_embed,hidden_size)
model(input_[0:3])

Results are :
tensor([[ 0.2726, -0.5882, -0.9438, -0.8380,  0.2866,  0.7537,  0.8387, -0.9315,
-0.3624, -0.6164,  0.6472,  0.3157, -0.9453,  0.6535,  0.5850, -0.7729],
[-0.1652, -0.9067, -0.7611,  0.2591,  0.0118, -0.1394,  0.8526, -0.1523,
-0.7598, -0.3685, -0.5124, -0.3204,  0.2357,  0.2204,  0.5002, -0.6450],
[-0.1652, -0.9067, -0.7611,  0.2591,  0.0118, -0.1394,  0.8526, -0.1523,
-0.7598, -0.3685, -0.5124, -0.3204,  0.2357,  0.2204,  0.5002, -0.6450]],
grad_fn=)
Now I got 3 hidden state for 3 sentences Now how to send those state into initial_state of decorder part/