class_docstr: SBD (Sub-band Discriminator) Block
class_docstr_tok: ["SBD","(","Sub-band","Discriminator",")","Block"]
code: def forward(self, x):
      fmap = []
      for _l in self.convs:
          x = _l(x)
          fmap.append(x)
      x = self.post_conv(x)  # @@
  
      return x, fmap
  
imports: import logging
  from typing import Any, Dict, List, Optional
  import torch
  import torch.nn.functional
  from torch.nn import Conv1d
  from torch.nn.utils import spectral_norm, weight_norm
  from espnet2.gan_svs.visinger2.visinger2_vocoder import MultiFrequencyDiscriminator
  from espnet2.gan_tts.hifigan.residual_block import ResidualBlock
  from espnet2.gan_tts.melgan.pqmf import PQMF
label_desc: Use image node_id 2 for calling the SBDBlock obj's underlying member method code with example usage: obj.forward(x) and returns: x,  fmap