App: remove Py2 code from several src/App .cpp files

src/App/ObjectIdentifier.cpp

@@ -1548,11 +1548,7 @@ Py::Object ObjectIdentifier::access(const ResolveResults &result, Py::Object *va
         GET_MODULE(re);
         break;
     case PseudoBuiltins:
-#if PY_MAJOR_VERSION < 3
-        GET_MODULE(__builtin__);
-#else
         GET_MODULE(builtins);
-#endif
         break;
     case PseudoMath:
         GET_MODULE(math);