diff --git a/stdlib/2/types.pyi b/stdlib/2/types.pyi
index e4df50d8e..87380b324 100644
--- a/stdlib/2/types.pyi
+++ b/stdlib/2/types.pyi
@@ -81,10 +81,11 @@ class ClassType: ...
 class UnboundMethodType:
     im_class = ...  # type: type
     im_func = ...  # type: FunctionType
-    im_self = ...  # type: Optional[object]
+    im_self = ...  # type: object
     __name__ = ...  # type: str
     __func__ = im_func
     __self__ = im_self
+    def __init__(self, func: Callable, obj: object) -> None: ...
     def __call__(self, *args: Any, **kwargs: Any) -> Any: ...
 
 class InstanceType:
diff --git a/stdlib/3/types.pyi b/stdlib/3/types.pyi
index 9894742a3..f9f46c5fd 100644
--- a/stdlib/3/types.pyi
+++ b/stdlib/3/types.pyi
@@ -140,6 +140,7 @@ class MethodType:
     __func__ = ...  # type: _StaticFunctionType
     __self__ = ...  # type: object
     __name__ = ...  # type: str
+    def __init__(self, func: Callable, obj: object) -> None: ...
     def __call__(self, *args: Any, **kwargs: Any) -> Any: ...
 class BuiltinFunctionType:
     __self__ = ...  # type: Union[object, ModuleType]