code: def export_string_int_label_encoder() -> None:
      node = onnx.helper.make_node(
          "LabelEncoder",
          inputs=["X"],
          outputs=["Y"],
          domain="ai.onnx.ml",
          keys_strings=["a", "b", "c"],
          values_int64s=[0, 1, 2],
          default_int64=42,
      )
      x = np.array(["a", "b", "d", "c", "g"]).astype(object)
      y = np.array([0, 1, 42, 2, 42]).astype(np.int64)
      expect(
          node,
          inputs=[x],
          outputs=[y],
          name="test_ai_onnx_ml_label_encoder_string_int",
      )
  
      node = onnx.helper.make_node(
          "LabelEncoder",
          inputs=["X"],
          outputs=["Y"],
          domain="ai.onnx.ml",
          keys_strings=["a", "b", "c"],
          values_int64s=[0, 1, 2],
      )
      x = np.array(["a", "b", "d", "c", "g"]).astype(object)
      y = np.array([0, 1, -1, 2, -1]).astype(np.int64)
      expect(
          node,
          inputs=[x],
          outputs=[y],
          name="test_ai_onnx_ml_label_encoder_string_int_no_default",
      )
  
file_path: onnx/onnx/backend/test/case/node/ai_onnx_ml/label_encoder.py
imports: import numpy
  import onnx
  from onnx.backend.test.case.base import Base
  from onnx.backend.test.case.node import expect
  from onnx.helper import make_tensor
label_desc: Use image node_id 1 for calling the LabelEncoder obj's underlying member method code with example usage: obj.export_string_int_label_encoder() without return types