Add doc string to type object.
diff --git a/Modules/parsermodule.c b/Modules/parsermodule.c
index bd1be62..50c1def 100644
--- a/Modules/parsermodule.c
+++ b/Modules/parsermodule.c
@@ -213,7 +213,18 @@
0, /* tp_as_mapping */
0, /* tp_hash */
0, /* tp_call */
- 0 /* tp_str */
+ 0, /* tp_str */
+ 0, /* tp_getattro */
+ 0, /* tp_setattro */
+
+ /* Functions to access object as input/output buffer */
+ 0, /* tp_as_buffer */
+
+ /* Space for future expansion */
+ 0, /* tp_xxx4 */
+
+ /* __doc__ */
+ "Intermediate representation of a Python parse tree."
}; /* PyAST_Type */