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diff --git a/sources/pyside6/libpyside/class_property.cpp b/sources/pyside6/libpyside/class_property.cpp
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+++ b/sources/pyside6/libpyside/class_property.cpp
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+/****************************************************************************
+**
+** Copyright (C) 2020 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of Qt for Python.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "pyside.h"
+#include "pysidestaticstrings.h"
+#include "feature_select.h"
+#include "class_property.h"
+
+#include <shiboken.h>
+#include <sbkstaticstrings.h>
+
+extern "C" {
+
+/*
+ * A `classproperty` is the same as a `property` but the `__get__()` and `__set__()`
+ * methods are modified to always use the object class instead of a concrete instance.
+ *
+ * Note: A "static property" as it is often called does not exist per se.
+ * Static methods do not receive anything when created. Static methods which
+ * should participate in a property must be turned into class methods, before.
+ * See function `createProperty` in `feature_select.cpp`.
+ */
+
+// `class_property.__get__()`: Always pass the class instead of the instance.
+static PyObject *PyClassProperty_get(PyObject *self, PyObject * /*ob*/, PyObject *cls)
+{
+    return PyProperty_Type.tp_descr_get(self, cls, cls);
+}
+
+// `class_property.__set__()`: Just like the above `__get__()`.
+static int PyClassProperty_set(PyObject *self, PyObject *obj, PyObject *value)
+{
+    PyObject *cls = PyType_Check(obj) ? obj : reinterpret_cast<PyObject *>(Py_TYPE(obj));
+    return PyProperty_Type.tp_descr_set(self, cls, value);
+}
+
+// The property `__doc__` default does not work for class properties
+// because PyProperty_Type.tp_init thinks this is a subclass which needs PyObject_SetAttr.
+// We call `__init__` while pretending to be a PyProperty_Type instance.
+static int PyClassProperty_init(PyObject *self, PyObject *args, PyObject *kwargs)
+{
+    auto hold = Py_TYPE(self);
+    Py_TYPE(self) = &PyProperty_Type;
+    auto ret =  PyProperty_Type.tp_init(self, args, kwargs);
+    Py_TYPE(self) = hold;
+    return ret;
+}
+
+static PyType_Slot PyClassProperty_slots[] = {
+    {Py_tp_getset,      nullptr},    // will be set below
+    {Py_tp_base,        reinterpret_cast<void *>(&PyProperty_Type)},
+    {Py_tp_descr_get,   reinterpret_cast<void *>(PyClassProperty_get)},
+    {Py_tp_descr_set,   reinterpret_cast<void *>(PyClassProperty_set)},
+    {Py_tp_init,        reinterpret_cast<void *>(PyClassProperty_init)},
+    {0, 0}
+};
+
+static PyType_Spec PyClassProperty_spec = {
+    "PySide6.PyClassProperty",
+    sizeof(propertyobject),
+    0,
+    Py_TPFLAGS_DEFAULT|Py_TPFLAGS_BASETYPE,
+    PyClassProperty_slots,
+};
+
+PyTypeObject *PyClassPropertyTypeF()
+{
+    static PyTypeObject *type = nullptr;
+    if (type == nullptr) {
+        // Provide the same `tp_getset`, which is not inherited.
+        PyClassProperty_slots[0].pfunc = PyProperty_Type.tp_getset;
+        type = reinterpret_cast<PyTypeObject *>(
+            PyType_FromSpec(&PyClassProperty_spec));
+    }
+    return type;
+}
+
+/*
+ * Types with class properties need to handle `Type.class_prop = x` in a specific way.
+ * By default, Python replaces the `class_property` itself, but for wrapped C++ types
+ * we need to call `class_property.__set__()` in order to propagate the new value to
+ * the underlying C++ data structure.
+ */
+static int SbkObjectType_meta_setattro(PyObject *obj, PyObject *name, PyObject *value)
+{
+    // Use `_PepType_Lookup()` instead of `PyObject_GetAttr()` in order to get the raw
+    // descriptor (`property`) instead of calling `tp_descr_get` (`property.__get__()`).
+    auto type = reinterpret_cast<PyTypeObject *>(obj);
+    PyObject *descr = _PepType_Lookup(type, name);
+
+    // The following assignment combinations are possible:
+    //   1. `Type.class_prop = value`              --> descr_set: `Type.class_prop.__set__(value)`
+    //   2. `Type.class_prop = other_class_prop`   --> setattro:  replace existing `class_prop`
+    //   3. `Type.regular_attribute = value`       --> setattro:  regular attribute assignment
+    const auto class_prop = reinterpret_cast<PyObject *>(PyClassPropertyTypeF());
+    const auto call_descr_set = descr && PyObject_IsInstance(descr, class_prop)
+                                && !PyObject_IsInstance(value, class_prop);
+    if (call_descr_set) {
+        // Call `class_property.__set__()` instead of replacing the `class_property`.
+        return Py_TYPE(descr)->tp_descr_set(descr, obj, value);
+    } else {
+        // Replace existing attribute.
+        return PyType_Type.tp_setattro(obj, name, value);
+    }
+}
+
+} // extern "C"
+
+/*
+ * These functions are added to the SbkObjectType_TypeF() dynamically.
+ */
+namespace PySide { namespace ClassProperty {
+
+void init()
+{
+    PyTypeObject *type = SbkObjectType_TypeF();
+    type->tp_setattro = SbkObjectType_meta_setattro;
+    Py_TYPE(PyClassPropertyTypeF()) = type;
+}
+
+} // namespace ClassProperty
+} // namespace PySide