code: def test_int(self):
      self._dll.tf_i.restype = c_int
      self._dll.tf_i.argtypes = (c_int,)
      self.assertEqual(self._dll.tf_i(-2147483646), -715827882)
      self.assertEqual(self.S(), -2147483646)
  
imports: import _ctypes_test
  import ctypes
  import unittest
  from ctypes import CDLL, c_byte, c_ubyte, c_char, c_short, c_ushort, c_int, c_uint, c_long, c_ulong, c_longlong, c_ulonglong, c_float, c_double, c_longdouble
label_desc: Use image node_id 11 for calling the CFunctions obj's underlying member method code with example usage: obj.test_int() without return types