code: def test_classmethod_decorator(self):
      glob = 1
  
      class Foo:
          @classmethod
          def f(cls):
              return glob
  
      func_map = free_vars_detect._detect_function_free_vars(Foo.f)
      self.assertLen(func_map.keys(), 1)
      self.assertIn("Foo.f", func_map.keys())
      free_vars = get_var_name(func_map["Foo.f"])
      self.assertSequenceEqual(free_vars, ["glob"])
  
imports: import functools
  import unittest
  from absl.testing import parameterized
  import numpy
  from tensorflow.core.function.capture import free_vars_detect
  from tensorflow.python.util import tf_decorator
label_desc: Use image node_id 23 for calling the FreeVarDetectionTest obj's underlying member method code with example usage: obj.test_classmethod_decorator() and returns: glob