diff -r a8799a63feb7 Modules/clinic/posixmodule.c.h
--- a/Modules/clinic/posixmodule.c.h	Mon Oct 31 19:51:58 2016 -0400
+++ b/Modules/clinic/posixmodule.c.h	Wed Nov 02 10:26:51 2016 +0200
@@ -954,7 +954,8 @@ exit:
 PyDoc_STRVAR(os__isdir__doc__,
 "_isdir($module, path, /)\n"
 "--\n"
-"\n");
+"\n"
+"Return true if the pathname refers to an existing directory.");
 
 #define OS__ISDIR_METHODDEF    \
     {"_isdir", (PyCFunction)os__isdir, METH_O, os__isdir__doc__},
@@ -5784,4 +5785,4 @@ exit:
 #ifndef OS_SET_HANDLE_INHERITABLE_METHODDEF
     #define OS_SET_HANDLE_INHERITABLE_METHODDEF
 #endif /* !defined(OS_SET_HANDLE_INHERITABLE_METHODDEF) */
-/*[clinic end generated code: output=9d5f831b23145d1e input=a9049054013a1b77]*/
+/*[clinic end generated code: output=7690b72549d2524e input=a9049054013a1b77]*/
diff -r a8799a63feb7 Modules/posixmodule.c
--- a/Modules/posixmodule.c	Mon Oct 31 19:51:58 2016 -0400
+++ b/Modules/posixmodule.c	Wed Nov 02 10:26:51 2016 +0200
@@ -3865,20 +3865,18 @@ os__getfinalpathname_impl(PyObject *modu
     return result;
 }
 
-PyDoc_STRVAR(posix__isdir__doc__,
-"Return true if the pathname refers to an existing directory.");
-
 /*[clinic input]
 os._isdir
 
     path: path_t
     /
 
+Return true if the pathname refers to an existing directory.
 [clinic start generated code]*/
 
 static PyObject *
 os__isdir_impl(PyObject *module, path_t *path)
-/*[clinic end generated code: output=75f56f32720836cb input=e794f12faab62a2a]*/
+/*[clinic end generated code: output=75f56f32720836cb input=5e0800149c0ad95f]*/
 {
     DWORD attributes;