Merged revisions 64842,64853,64856,64945 via svnmerge from
svn+ssh://pythondev@svn.python.org/python/trunk

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  r64842 | robert.schuppenies | 2008-07-10 15:43:26 +0200 (Thu, 10 Jul 2008) | 2 lines

  Fixed Issue3122 and extended sys.getsizeof tests for built-in types.
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  r64853 | robert.schuppenies | 2008-07-10 17:24:04 +0200 (Thu, 10 Jul 2008) | 3 lines

  Added additional __sizeof__ implementations and addressed comments made in
  Issue3122.
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  r64856 | robert.schuppenies | 2008-07-10 19:13:55 +0200 (Thu, 10 Jul 2008) | 3 lines

  Added garbage collector overhead and optional default return value to
  sys.getsizeof.
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  r64945 | robert.schuppenies | 2008-07-14 10:42:18 +0200 (Mon, 14 Jul 2008) | 2 lines

  Fixed test failure on Win64 machines.
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diff --git a/Doc/library/sys.rst b/Doc/library/sys.rst
index 42c36a6..f92b1e4 100644
--- a/Doc/library/sys.rst
+++ b/Doc/library/sys.rst
@@ -331,13 +331,20 @@
    :func:`setrecursionlimit`.
 
 
-.. function:: getsizeof(object)
+.. function:: getsizeof(object[, default])
 
    Return the size of an object in bytes. The object can be any type of
    object. All built-in objects will return correct results, but this
-   does not have to hold true for third-party extensions as it is implementation 
+   does not have to hold true for third-party extensions as it is implementation
    specific.
 
+   The *default* argument allows to define a value which will be returned
+   if the object type does not provide means to retrieve the size and would
+   cause a `TypeError`. 
+
+   func:`getsizeof` calls the object's __sizeof__ method and adds an additional
+   garbage collector overhead if the object is managed by the garbage collector.
+
    .. versionadded:: 2.6