code: def forward(self, x):
      return self.analysis(x)
  
file_path: TTS/TTS/vocoder/layers/pqmf.py
imports: import numpy
  import torch
  import torch.nn.functional
  from scipy import signal
label_desc: Use image node_id 2 for calling the PQMF obj's underlying member method code with example usage: obj.forward(x) and returns: self