code: def test_isnamedtuple(self):
      nt = collections.namedtuple("TestNamedTuple", ["a", "b"])
  
      class NotANamedTuple(tuple):
          pass
  
      self.assertTrue(inspect_utils.isnamedtuple(nt))
      self.assertFalse(inspect_utils.isnamedtuple(NotANamedTuple))
  
imports: import abc
  import collections
  import functools
  import textwrap
  import types
  from tensorflow.python import lib
  from tensorflow.python.autograph.pyct import inspect_utils
  from tensorflow.python.autograph.pyct.testing import basic_definitions
  from tensorflow.python.autograph.pyct.testing import decorators
  from tensorflow.python.framework import constant_op
  from tensorflow.python.platform import test
label_desc: Use image node_id 3 for calling the InspectUtilsTest obj's underlying member method code with example usage: obj.test_isnamedtuple() without return types