Extension modules might want to have their own tp_free.

src/capi/typeobject.cpp

@@ -3247,7 +3247,6 @@ extern "C" int PyType_Ready(PyTypeObject* cls) noexcept {
                        | Py_TPFLAGS_DICT_SUBCLASS | Py_TPFLAGS_BASE_EXC_SUBCLASS | Py_TPFLAGS_TYPE_SUBCLASS;
     RELEASE_ASSERT((cls->tp_flags & ~ALLOWABLE_FLAGS) == 0, "");
 
-    RELEASE_ASSERT(cls->tp_free == NULL || cls->tp_free == PyObject_Del || cls->tp_free == PyObject_GC_Del, "");
     RELEASE_ASSERT(cls->tp_is_gc == NULL, "");
     RELEASE_ASSERT(cls->tp_mro == NULL, "");
     RELEASE_ASSERT(cls->tp_cache == NULL, "");