code: def forward(self, input, hx=None):
      if isinstance(input, PackedSequence):
          return self.forward_packed(input, hx)
      else:
          return self.forward_tensor(input, hx)
  
imports: import warnings
  from typing import List, Optional, Tuple
  import torch
  from torch import _VF, Tensor
  from torch.nn.utils.rnn import PackedSequence
label_desc: Use image node_id 5 for calling the QuantizedGRU obj's underlying member method code with example usage: obj.forward(input, hx) and returns: self, self