code: def encode(self,
                 data: mx.sym.Symbol,
                 data_length: Optional[mx.sym.Symbol],
                 seq_len: int) -> Tuple[mx.sym.Symbol, mx.sym.Symbol, int]:
          
          outputs, _ = self.rnn.unroll(seq_len, inputs=data, merge_outputs=True, layout=self.layout)
  
          return outputs, data_length, seq_len
docs: Encodes data given sequence lengths of individual examples and maximum sequence length.
  
          :param data: Input data.
          :param data_length: Vector with sequence lengths.
          :param seq_len: Maximum sequence length.
          :return: Encoded versions of input data (data, data_length, seq_len).