add_to_worklist(use.getOwner()->getResult(use.getOperandNumber()));
        continue;
      }
      // Refining the tensor list element type might change the output of
      // TensorListElementShape which is expected to be the originally assigned
      // shape to TensorList init ops. So replace it with the original element
      // shape value.
      if (auto tl_element_shape =

  );

  TF_DerivedOperandTypeAttr shape_type = TF_DerivedOperandTypeAttr<1>;
  TF_DerivedResultTypeAttr element_dtype = TF_DerivedResultTypeAttr<0>;
}

def TF_TensorListElementShapeOp : TF_Op<"TensorListElementShape", [Pure]> {
  let summary = "The shape of the elements of the given list, as a tensor.";

  let description = [{
input_handle: the list
  element_shape: the shape of elements of the list
  }];