code: def test_builder_threshold_eval(self):
      val = np.array(
          [[-1.2, 2, -3.4], [4.5, -5, 6.7]], dtype=np.float32
      )
      v = mb.threshold(x=val, alpha=1.0)
      expected_outputs = np.array(
          [[1.0, 2, 1.0], [4.5, 1.0, 6.7]], dtype=np.float32
      )
  
      np.testing.assert_allclose(
          expected_outputs, v.val, atol=1e-04, rtol=1e-05
      )
  
imports: import itertools
  import numpy
  import pytest
  import scipy
  from coremltools.converters.mil.mil import Builder
  from coremltools.converters.mil.mil import Function, get_new_symbol, types
  from coremltools.converters.mil.mil.ops.tests.iOS14 import backends
  from coremltools.converters.mil.mil.ops.tests.testing_utils import run_compare_builder
  from coremltools.converters.mil.mil.types.symbolic import is_compatible_symbolic_vector
  from coremltools.converters.mil.testing_reqs import compute_units
  from coremltools.converters.mil.testing_utils import ssa_fn
label_desc: Use image node_id 26 for calling the TestElementwiseUnary obj's underlying member method code with example usage: obj.test_builder_threshold_eval() without return types