diff -r 3d328ee18612 -r 2f08a506f8ee Doc/library/types.rst
--- a/Doc/library/types.rst	Mon Jan 30 13:56:20 2017 +0300
+++ b/Doc/library/types.rst	Mon Jan 30 12:16:49 2017 +0100
@@ -131,7 +131,30 @@
    methods of built-in classes.  (Here, the term "built-in" means "written in
    C".)
 
+   
+.. data:: SlotWrapperType
 
+   The type of methods of some built-in data types and base classes such as
+   :meth:`object.__init__` or :meth:`object.__lt__`.
+
+   .. versionadded:: 3.7
+
+   
+.. data:: MethodWrapperType
+
+   The type of *bound* methods of some built-in data types and base classes.
+   For example it is the type of :code:`object().__str__`.
+
+   .. versionadded:: 3.7
+
+   
+.. data:: MethodDescriptorType
+
+   The type of methods of some built-in data types such as :meth:`str.join`.
+
+   .. versionadded:: 3.7
+
+   
 .. class:: ModuleType(name, doc=None)
 
    The type of :term:`modules <module>`. Constructor takes the name of the
diff -r 3d328ee18612 -r 2f08a506f8ee Lib/types.py
--- a/Lib/types.py	Mon Jan 30 13:56:20 2017 +0300
+++ b/Lib/types.py	Mon Jan 30 12:16:49 2017 +0100
@@ -36,6 +36,10 @@
 BuiltinFunctionType = type(len)
 BuiltinMethodType = type([].append)     # Same as BuiltinFunctionType
 
+SlotWrapperType = type(object.__init__)
+MethodWrapperType = type(object().__str__)
+MethodDescriptorType = type(str.join)
+
 ModuleType = type(sys)
 
 try: