code: def test_pad_with_dynamic_input_shape(self):
      g = self.create_empty_graph()
      input = g.addInput()
      input.setType(
          input.type()
          .with_dtype(torch.float)
          .with_sizes([3, None, None])
      )
      constant = self.insert_tensor_constant(
          g, torch.ones(6, dtype=torch.long)
      )
      none = g_op(g, "prim::Constant").setType(torch.NoneType.get())
      pad = g_op(g, "Pad", input, constant, none, mode_s="constant")
      self.run_test(
          g, pad.node(), expect_tensor("Float", shape=(5, None, None))
      )
  
imports: import io
  import numpy
  import onnx
  import pytorch_test_common
  import torch
  from pytorch_test_common import skipIfUnsupportedMinOpsetVersion
  from torch.onnx import _constants, utils
  from torch.onnx._globals import GLOBALS
  from torch.onnx._internal import jit_utils
  from torch.testing._internal import common_utils
label_desc: Use image node_id 19 for calling the TestONNXShapeInference obj's underlying member method code with example usage: obj.test_pad_with_dynamic_input_shape() without return types