docstr: The private function to design the specific RNN models.
  MUST be override by subclass
docstr_tok: ["The","private","function","to","design","the","specific","RNN","models",".","MUST","be","override","by","subclass"]
code: def _build_rnn(self, **kwargs):
      """
      The private function to design the specific RNN models.
      MUST be override by subclass
      """
      raise NotImplementedError()
  
imports: import torch.nn
label_desc: Use image node_id 2 for calling the RNNDecoderBase obj's underlying member method code with example usage: obj._build_rnn() without return types