code: def _unpack(self):
      self.packed_tensor_ptr.set_(
          torch.fbgemm_pack_quantized_matrix(self.weight)
      )
  
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 2 for calling the QuantizedLinear obj's underlying member method code with example usage: obj._unpack() without return types