--- a/Modules/parsermodule.c	Thu Aug 02 20:37:12 2012 +0200
+++ b/Modules/parsermodule.c	Fri Aug 03 14:28:37 2012 +0200
@@ -167,6 +167,7 @@
 
 
 static void parser_free(PyST_Object *st);
+static PyObject* parser_sizeof(PyST_Object *, void *);
 static PyObject* parser_richcompare(PyObject *left, PyObject *right, int op);
 static PyObject* parser_compilest(PyST_Object *, PyObject *, PyObject *);
 static PyObject* parser_isexpr(PyST_Object *, PyObject *, PyObject *);
@@ -187,7 +188,8 @@
         PyDoc_STR("Creates a list-tree representation of this ST.")},
     {"totuple",         (PyCFunction)parser_st2tuple,   PUBLIC_METHOD_TYPE,
         PyDoc_STR("Creates a tuple-tree representation of this ST.")},
-
+    {"__sizeof__",      (PyCFunction)parser_sizeof,     METH_NOARGS,
+        PyDoc_STR("Returns size in memory, in bytes.")},
     {NULL, NULL, 0, NULL}
 };
 
@@ -361,6 +363,15 @@
     PyObject_Del(st);
 }
 
+static PyObject *
+parser_sizeof(PyST_Object *st, void *unused)
+{
+    Py_ssize_t res;
+
+    res = sizeof(PyST_Object) + _PyNode_SizeOf(st->st_node);
+    return PyLong_FromSsize_t(res);
+}
+
 
 /*  parser_st2tuple(PyObject* self, PyObject* args, PyObject* kw)
  *