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diff --git a/lib/python2.7/ctypes/test/test_objects.py b/lib/python2.7/ctypes/test/test_objects.py
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+++ b/lib/python2.7/ctypes/test/test_objects.py
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+r'''
+This tests the '_objects' attribute of ctypes instances.  '_objects'
+holds references to objects that must be kept alive as long as the
+ctypes instance, to make sure that the memory buffer is valid.
+
+WARNING: The '_objects' attribute is exposed ONLY for debugging ctypes itself,
+it MUST NEVER BE MODIFIED!
+
+'_objects' is initialized to a dictionary on first use, before that it
+is None.
+
+Here is an array of string pointers:
+
+>>> from ctypes import *
+>>> array = (c_char_p * 5)()
+>>> print array._objects
+None
+>>>
+
+The memory block stores pointers to strings, and the strings itself
+assigned from Python must be kept.
+
+>>> array[4] = 'foo bar'
+>>> array._objects
+{'4': 'foo bar'}
+>>> array[4]
+'foo bar'
+>>>
+
+It gets more complicated when the ctypes instance itself is contained
+in a 'base' object.
+
+>>> class X(Structure):
+...     _fields_ = [("x", c_int), ("y", c_int), ("array", c_char_p * 5)]
+...
+>>> x = X()
+>>> print x._objects
+None
+>>>
+
+The'array' attribute of the 'x' object shares part of the memory buffer
+of 'x' ('_b_base_' is either None, or the root object owning the memory block):
+
+>>> print x.array._b_base_ # doctest: +ELLIPSIS
+<ctypes.test.test_objects.X object at 0x...>
+>>>
+
+>>> x.array[0] = 'spam spam spam'
+>>> x._objects
+{'0:2': 'spam spam spam'}
+>>> x.array._b_base_._objects
+{'0:2': 'spam spam spam'}
+>>>
+
+'''
+
+import unittest, doctest, sys
+
+import ctypes.test.test_objects
+
+class TestCase(unittest.TestCase):
+    if sys.hexversion > 0x02040000:
+        # Python 2.3 has no ELLIPSIS flag, so we don't test with this
+        # version:
+        def test(self):
+            doctest.testmod(ctypes.test.test_objects)
+
+if __name__ == '__main__':
+    if sys.hexversion > 0x02040000:
+        doctest.testmod(ctypes.test.test_objects)