def __call__(self, inputs, valid_length=None, states=None):  
return super(Seq2SeqEncoder, self).__call__(inputs, valid_length, states)<EOL>
Encode the input sequence.

        Parameters
        ----------
        inputs : NDArray
            The input sequence, Shape (batch_size, length, C_in).
        valid_length : NDArray or None, default None
            The valid length of the input sequence, Shape (batch_size,). This is used when the
            input sequences are padded. If set to None, all elements in the sequence are used.
        states : list of NDArrays or None, default None
            List that contains the initial states of the encoder.

        Returns
        -------
        outputs : list
            Outputs of the encoder.