code: def test_an_integer(self):
      ctdll = CDLL(_ctypes_test.__file__)
      an_integer = c_int.in_dll(ctdll, "an_integer")
      x = an_integer.value
      self.assertEqual(x, ctdll.get_an_integer())
      an_integer.value *= 2
      self.assertEqual(x * 2, ctdll.get_an_integer())
  
file_path: catboost/contrib/tools/python/src/Lib/ctypes/test/test_values.py
imports: import unittest
  import sys
  from ctypes import *
  import _ctypes_test
label_desc: Use image node_id 1 for calling the ValuesTestCase obj's underlying member method code with example usage: obj.test_an_integer() without return types