diff -r c5f6d122ddd6 Doc/library/types.rst
--- a/Doc/library/types.rst	Wed Sep 28 00:53:54 2016 +0200
+++ b/Doc/library/types.rst	Thu Jan 26 22:09:25 2017 +0100
@@ -124,6 +124,13 @@
    C".)
 
 
+.. data:: SlotWrapperType
+          MethodWrapperType
+
+   The type of methods of some fundamental built-in data types and base classes (such as :meth:`object.__init__` or `object.__lt__`).
+   The second one is the type of these methods once they are bound to an instance.
+
+
 .. class:: ModuleType(name, doc=None)
 
    The type of :term:`modules <module>`. Constructor takes the name of the
diff -r c5f6d122ddd6 Lib/types.py
--- a/Lib/types.py	Wed Sep 28 00:53:54 2016 +0200
+++ b/Lib/types.py	Thu Jan 26 22:09:25 2017 +0100
@@ -36,6 +36,9 @@
 BuiltinFunctionType = type(len)
 BuiltinMethodType = type([].append)     # Same as BuiltinFunctionType
 
+SlotWrapperType = type(object.__init__)
+MethodWrapperType = type(object().__str__)
+
 ModuleType = type(sys)
 
 try: