Issue #13645: pyc files now contain the size of the corresponding source
code, to avoid timestamp collisions (especially on filesystems with a low
timestamp resolution) when checking for freshness of the bytecode.
diff --git a/Python/Python-ast.c b/Python/Python-ast.c
index 3121eb1..2882bbc 100644
--- a/Python/Python-ast.c
+++ b/Python/Python-ast.c
@@ -2800,7 +2800,7 @@
if (!result) goto failed;
value = ast2obj_int(o->v.Yield.is_from);
if (!value) goto failed;
- if (PyObject_SetAttrString(result, "is_from", value) == -1)
+ if (_PyObject_SetAttrId(result, &PyId_is_from, value) == -1)
goto failed;
Py_DECREF(value);
value = ast2obj_expr(o->v.Yield.value);