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Author: Skylion007

include/pybind11/detail/class.h

@@ -543,8 +543,12 @@ extern "C" inline int pybind11_clear(PyObject *self) {
 inline void enable_dynamic_attributes(PyHeapTypeObject *heap_type) {
     auto *type = &heap_type->ht_type;
     type->tp_flags |= Py_TPFLAGS_HAVE_GC;
+#if PY_VERSION_HEX < 0x030B0000
     type->tp_dictoffset = type->tp_basicsize;           // place dict at the end
     type->tp_basicsize += (ssize_t) sizeof(PyObject *); // and allocate enough space for it
+#else
+    type->tp_flags |= Py_TPFLAGS_MANAGED_DICT;
+#endif
     type->tp_traverse = pybind11_traverse;
     type->tp_clear = pybind11_clear;