code: def test_singledispatch2(self):
      if hasattr(functools, "singledispatch"):
          doc.singledispatch_example2()
  
imports: from __future__ import absolute_import
  import sys
  import doctest
  import unittest
  import decimal
  import inspect
  import functools
  import collections
  from collections import defaultdict
  from decorator import dispatch_on, contextmanager, decorator
label_desc: Use image node_id 3 for calling the DocumentationTestCase obj's underlying member method code with example usage: obj.test_singledispatch2() without return types