Some style nits. Also clarify in the docstrings what __sizeof__ does.
diff --git a/Objects/longobject.c b/Objects/longobject.c
index 5876495..c9d138b 100644
--- a/Objects/longobject.c
+++ b/Objects/longobject.c
@@ -3467,7 +3467,7 @@
 	{"__getnewargs__",	(PyCFunction)long_getnewargs,	METH_NOARGS},
         {"__format__", (PyCFunction)long__format__, METH_VARARGS},
 	{"__sizeof__",	(PyCFunction)long_sizeof, METH_NOARGS,
-	 "Returns size in bytes"},
+	 "Returns size in memory, in bytes"},
 	{NULL,		NULL}		/* sentinel */
 };