code: def test_definitions_in_except_block_of_raising_try(self):
      def test_fn():
          try:
              raise ValueError()
          except ValueError:
              a = None
          if a:  # pylint:disable=using-constant-test
              a = None
          return a
  
      node = self._parse_and_analyze(test_fn)
      fn_body = node.body
  
      self.assertHasDefs(fn_body[1].test, 1)
      self.assertHasDefs(fn_body[1].body[0].targets[0], 1)
      self.assertHasDefs(fn_body[2].value, 2)
  
      self.assertHasDefinedIn(fn_body[1], ("a",))
  
imports: from tensorflow.python.autograph.pyct import anno
  from tensorflow.python.autograph.pyct import cfg
  from tensorflow.python.autograph.pyct import naming
  from tensorflow.python.autograph.pyct import parser
  from tensorflow.python.autograph.pyct import qual_names
  from tensorflow.python.autograph.pyct import transformer
  from tensorflow.python.autograph.pyct.static_analysis import activity
  from tensorflow.python.autograph.pyct.static_analysis import reaching_definitions
  from tensorflow.python.platform import test
label_desc: Use image node_id 18 for calling the ReachingDefinitionsAnalyzerTest obj's underlying member method code with example usage: obj.test_definitions_in_except_block_of_raising_try() and returns: a