pyqtProperty setter always raises an error

Bug Report

It seems that Mypy is not enjoying pyqtProperty setters. Someone already asked on the Qt mailing-list.

To Reproduce

from PyQt5.QtCore import QObject, pyqtProperty, pyqtSignal


class FeatureModel(QObject):

    stateChanged = pyqtSignal()

    def __init__(self, enabled: bool, /) -> None:
        super().__init__()
        self._enabled = enabled

    @pyqtProperty(bool, notify=stateChanged)
    def enabled(self):
        return self._enabled

    @enabled.setter
    def enabled(self, enabled):
        self._enabled = enabled
        self.stateChanged.emit()

Expected Behavior

Mypy should be happy.

Actual Behavior

$ python -m mypy file.py
file.py:16: error: Name 'enabled' already defined on line 12
Found 1 error in 1 file (checked 1 source file)

Your Environment

• Mypy version used: 0.790
• Mypy command-line flags: None
• Mypy configuration options from mypy.ini (and other config files): None
• Python version used: 3.8.6
• Operating system and version: macOS Big Sur (arm64) and Windows 10.

Start with the provided file.py reproducer and run python -m mypy file.py to confirm the duplicate-definition error. Then inspect how mypy handles pyqtProperty and its .setter form; done means the example type-checks without the reported error.