code: def build_model(self, dr_rate=0, path=None):
          
          #set network
          self.net = LipNet(dr_rate)
          self.net.hybridize()
          self.net.initialize(ctx=self.ctx)
  
          if path is not None:
              self.load_model(path)
  
          #set optimizer
          self.loss_fn = gluon.loss.CTCLoss()
          self.trainer = gluon.Trainer(self.net.collect_params(), \
                                       optimizer='SGD')
docs: Description : build network