[Python] Python multiple inheretance with property

Consider the following code:

from typing import Any

from PyQt6.QtCore import pyqtSignal
from PyQt6.QtGui import QFont
from PyQt6.QtWidgets import QApplication, QWidget
from qtconsole.rich_jupyter_widget import RichJupyterWidget


class BasePane:
"""Represents the common aspects of a pane."""

def set_font_size(self, new_size: int = 10) -> None:
"""Set font size."""
raise NotImplementedError

def set_theme(self, theme: str) -> None:
"""Set theme."""


class JupyterREPLPane(RichJupyterWidget, QWidget, BasePane):
"""
REPL = Read, Evaluate, Print, Loop.

Displays a Jupyter iPython session.
"""

on_append_text = pyqtSignal(bytes)

def __init__(self, theme: str = "day", *args: Any, **kw: Any) -> None: # noqa: ANN401
"""Initialise the Jupyter REPL pane."""
super().__init__(self, *args, **kw)
self.font = QFont("Helvetica")
self.console_height = 10
self.set_theme(theme)

def _append_plain_text(
self, text: str, before_prompt: bool = False
) -> None:
"""Ensures appended text is emitted as a signal with associated bytes."""
super()._append_plain_text(text, before_prompt)]
self.on_append_text.emit(text.encode("utf-8"))

def set_font_size(self, new_size: int = 10) -> None:
"""Set the font size for all the textual elements in this pane."""
self.font_size = new_size
font: QFont = self.font
font.setPointSize(new_size)
self.font = font
print(font)

def setFocus(self) -> None:
"""
Override base setFocus so the focus happens to the embedded _control
within this widget.
"""
self._control.setFocus()


app = QApplication([])
pane = JupyterREPLPane()
pane.set_font_size(12)


For reference, font inherited from RichJupyterWidget:

font = property(_get_font, _set_font)


font inherited from QWidget:

def font(self) -> QtGui.QFont:


It runs fine (Python 3.13):

<PyQt6.QtGui.QFont object at 0x7f62121de650>


Then my first question: Is simply using self.font a good practice?

And if I change the code to:

def set_font_size(self, new_size: int = 10) -> None:
...
font = RichJupyterWidget.font
...


Then an error ocurrs:

Traceback (most recent call last):
File "/Data/mu/test_multiple.py", line 61, in <module>
pane.set_font_size(12)
~~~~~~~~~~~~~~~~~~^^^^
File "/Data/mu/test_multiple.py", line 47, in set_font_size
font.setPointSize(new_size)
^^^^^^^^^^^^^^^^^
AttributeError: 'property' object has no attribute 'setPointSize'


So, is there any simple syntax that can solve this problem? Similar to calling font inherited from QWidget:

QWidget.font(self)


The only one I could think of:

RichJupyterWidget.font.__get__(self)


It doesn't seem like a graceful way to use properties.

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