code: def linear_prepack(g: jit_utils.GraphContext, weight, bias):
      # Mapping to a dummy caffe2 prepack node.
      # During the onnx -> c2 conversion we can look up original weight and bias
      # from this node
      output = g.op("_caffe2::WeightPrepack", weight, bias)
      symbolic_helper._quantized_ops.add(output)
      return output
  
imports: import importlib
  import inspect
  from torch.onnx import symbolic_helper, symbolic_opset9
  from torch.onnx._internal import jit_utils, registration
label_desc: Use image node_id 5 for calling a global function with example usage: linear_prepack(g, weight, bias) and returns: output