code: def export_tril_out_neg() -> None:
      node = onnx.helper.make_node(
          "Trilu",
          inputs=["x", "k"],
          outputs=["y"],
          upper=0,
      )
  
      x = np.random.randint(10, size=(4, 5)).astype(np.int64)
      k = np.array(-7).astype(np.int64)
      # X:
      #  [[4, 7, 3, 7, 9],
      #   [1, 2, 8, 6, 9],
      #   [9, 4, 1, 8, 7],
      #   [4, 3, 4, 2, 4]]
      # expect result:
      #  [[0, 0, 0, 0, 0],
      #   [0, 0, 0, 0, 0],
      #   [0, 0, 0, 0, 0],
      #   [0, 0, 0, 0, 0]]
      y = tril_reference_implementation(x, int(k))
      expect(node, inputs=[x, k], outputs=[y], name="test_tril_out_neg")
  
imports: import numpy
  import onnx
  from onnx.backend.test.case.base import Base
  from onnx.backend.test.case.node import expect
label_desc: Use image node_id 12 for calling the Trilu obj's underlying member method code with example usage: obj.export_tril_out_neg() without return types