code: def setup_test_case(self):
      class Model(chainer.Chain):
          def __init__(self, ops):
              super(Model, self).__init__()
              self.ops = ops
  
          def __call__(self, a):
              if not isinstance(a, chainer.Variable):
                  a = chainer.Variable(a)
              return eval(self.ops)
  
      self.model = Model(self.ops)
      self.a = input_generator.positive_increasing(2, 3) / 10.0
  
      name = self.op_name.lower()
      if hasattr(self, "condition"):
          name += "_" + self.condition
      self.name = name
  
      skip_opset_version = []
      if (
          self.op_name == "Cosh"
          or self.op_name == "Sinh"
          or self.op_name == "Sign"
      ):
          skip_opset_version.append(7)
          skip_opset_version.append(8)
  
      if self.op_name == "BroadcastTo":
          skip_opset_version.append(7)
  
      self.skip_opset_version = skip_opset_version
  
imports: import chainer
  import chainer.functions
  from chainer import testing
  from chainer.testing import attr
  import numpy
  import pytest
  from onnx_chainer.testing import input_generator
  from onnx_chainer_tests.helper import ONNXModelTest
label_desc: Use image node_id 1 for calling the TestUnaryMathOperators obj's underlying member method code with example usage: obj.setup_test_case() and returns: eval