add PYSTON_NOEXCEPT to the header, and add implementations (that throw unimplemented)

from_cpython/Include/object.h

@@ -558,10 +558,10 @@ extern int _PyObject_SlotCompare(PyObject *, PyObject *);
 /* Same as PyObject_Generic{Get,Set}Attr, but passing the attributes
    dict as the last parameter. */
 PyAPI_FUNC(PyObject *)
-_PyObject_GenericGetAttrWithDict(PyObject *, PyObject *, PyObject *);
+_PyObject_GenericGetAttrWithDict(PyObject *, PyObject *, PyObject *) PYSTON_NOEXCEPT;
 PyAPI_FUNC(int)
 _PyObject_GenericSetAttrWithDict(PyObject *, PyObject *,
-                                 PyObject *, PyObject *);
+                                 PyObject *, PyObject *) PYSTON_NOEXCEPT;
 
 
 /* PyObject_Dir(obj) acts like Python __builtin__.dir(obj), returning a

src/runtime/capi.cpp

@@ -270,6 +270,16 @@ extern "C" PyObject* PyObject_GenericGetAttr(PyObject* o, PyObject* name) noexce
     }
 }
 
+extern "C" PyObject* _PyObject_GenericGetAttrWithDict(PyObject* obj, PyObject* name, PyObject* dict) noexcept {
+    Py_FatalError("unimplemented");
+}
+
+extern "C" int _PyObject_GenericSetAttrWithDict(PyObject* obj, PyObject* name, PyObject* value,
+                                                PyObject* dict) noexcept {
+    Py_FatalError("unimplemented");
+}
+
+
 extern "C" PyObject* PyObject_GetItem(PyObject* o, PyObject* key) noexcept {
     try {
         return getitem(o, key);