bpo-32571: Avoid raising unneeded AttributeError and silencing it in C code (GH-5222)

Add two new private APIs: _PyObject_LookupAttr() and _PyObject_LookupAttrId()

1 files changed, 4 insertions, 6 deletions

diff --git a/Modules/itertoolsmodule.c b/Modules/itertoolsmodule.c
index 985915f09d..1113fb6b76 100644
--- a/Modules/itertoolsmodule.c
+++ b/Modules/itertoolsmodule.c
@@ -830,17 +830,15 @@ tee(PyObject *self, PyObject *args)
         return NULL;
     }
 
-    copyfunc = _PyObject_GetAttrId(it, &PyId___copy__);
-    if (copyfunc != NULL) {
-        copyable = it;
-    }
-    else if (!PyErr_ExceptionMatches(PyExc_AttributeError)) {
+    if (_PyObject_LookupAttrId(it, &PyId___copy__, &copyfunc) < 0) {
         Py_DECREF(it);
         Py_DECREF(result);
         return NULL;
     }
+    if (copyfunc != NULL) {
+        copyable = it;
+    }
     else {
-        PyErr_Clear();
         copyable = tee_fromiterable(it);
         Py_DECREF(it);
         if (copyable == NULL) {