class_docstr: Decoder module of Spectrogram prediction network.
  
  This is a module of decoder of Spectrogram prediction network in Singing Tacotron,
  which described in `https://arxiv.org/pdf/2202.07907v1.pdf`_.
  The decoder generates the sequence of
  features from the sequence of the hidden states.
  
  .. _`Singing-Tacotron: Global Duration Control Attention and Dynamic
  Filter for End-to-end Singing Voice Synthesis`:
     https://arxiv.org/pdf/2202.07907v1.pdf
code: def _zero_state(self, hs):
      init_hs = hs.new_zeros(hs.size(0), self.lstm[0].hidden_size)
      return init_hs
  
file_path: espnet/espnet2/svs/singing_tacotron/decoder.py
imports: import six
  import torch
  import torch.nn.functional
  from espnet.nets.pytorch_backend.rnn.attentions import AttForwardTA
  from espnet.nets.pytorch_backend.tacotron2.decoder import Postnet, Prenet, ZoneOutCell
label_desc: Use image node_id 2 for calling the Decoder obj's underlying member method code with example usage: obj._zero_state(hs) and returns: init_hs