docstr: Test that model inference handles unknown ops.
  This special treatment is to support custom ops.
  See comments in shape inference code for details.
docstr_tok: ["Test","that","model","inference","handles","unknown","ops",".","This","special","treatment","is","to","support","custom","ops",".","See","comments","in","shape","inference","code","for","details","."]
code: def test_unknown_op(self):
      """Test that model inference handles unknown ops.
      This special treatment is to support custom ops.
      See comments in shape inference code for details.
      """
      model = """
              <ir_version: 7, opset_import: [ "" : 17]>
              agraph (float[N] x) => (y)
              {
                  y = SomeUnknownOp (x)
              }
          """
      # No output types are inferred for unknown ops.
      # But ensure that the inference does not fail.
      self._check(model)
  
file_path: onnx/onnx/test/model_inference_test.py
imports: import typing
  import unittest
  import onnx
  import onnx.parser
  import onnx.shape_inference
label_desc: Use image node_id 3 for calling the TestModelInference obj's underlying member method code with example usage: obj.test_unknown_op() without return types