code: def zero_grad(self, set_to_none=False):
      self.optimizer_d.zero_grad(set_to_none)
      self.optimizer_g.zero_grad(set_to_none)
  
imports: import os
  import sys
  import torch
  import torchaudio
  import speechbrain
  from pesq import pesq
  from hyperpyyaml import load_hyperpyyaml
  from speechbrain.utils.metric_stats import MetricStats
  from speechbrain.nnet.loss.stoi_loss import stoi_loss
  from speechbrain.utils.distributed import run_on_main
label_desc: Use image node_id 9 for calling the SEBrain obj's underlying member method code with example usage: obj.zero_grad(set_to_none) without return types