code: def test_nested_initializers(self):
      # test initializing nested structures
      class Phone(Structure):
          _fields_ = [("areacode", c_char * 6), ("number", c_char * 12)]
  
      class Person(Structure):
          _fields_ = [
              ("name", c_char * 12),
              ("phone", Phone),
              ("age", c_int),
          ]
  
      p = Person(b"Someone", (b"1234", b"5678"), 5)
  
      self.assertEqual(p.name, b"Someone")
      self.assertEqual(p.phone.areacode, b"1234")
      self.assertEqual(p.phone.number, b"5678")
      self.assertEqual(p.age, 5)
  
imports: import _ctypes_test
  from platform import architecture
  import struct
  import sys
  import unittest
  from ctypes import CDLL, Array, Structure, Union, POINTER, sizeof, byref, alignment, c_void_p, c_char, c_wchar, c_byte, c_ubyte, c_uint8, c_uint16, c_uint32, c_short, c_ushort, c_int, c_uint, c_long, c_ulong, c_longlong, c_ulonglong, c_float, c_double
  from ctypes.util import find_library
  from struct import calcsize
  from collections import namedtuple
  from test import support
  from ._support import _CData, PyCStructType, Py_TPFLAGS_DISALLOW_INSTANTIATION, Py_TPFLAGS_IMMUTABLETYPE
label_desc: Use image node_id 16 for calling the StructureTestCase obj's underlying member method code with example usage: obj.test_nested_initializers() without return types