Added garbage collector overhead and optional default return value to
sys.getsizeof.
diff --git a/Doc/library/sys.rst b/Doc/library/sys.rst
index 22397f2..871cec7 100644
--- a/Doc/library/sys.rst
+++ b/Doc/library/sys.rst
@@ -393,13 +393,20 @@
: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