code: def test_cast(self):
      # Test cast with input of unknown scalar type.
      g = self.create_empty_graph()
      input = g.addInput()
      cast_out = g_op(g, "Cast", input, to_i=1)
      self.run_test(g, cast_out.node(), expect_tensor("Float"))
  
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 5 for calling the TestONNXShapeInference obj's underlying member method code with example usage: obj.test_cast() without return types