TypeError on initialization of PyQt5 QtWidgets.QApplication

[casimir7]

Hello spyder-kernels team.
Thanks for your work!
I stumbled across the following

Problem:

On my system:
Fedora 33,
Python 3.9
Spyder 4.1.5
PyQt5 5.15.0,

I cannot instantiate QApplication in Spyder. As a test case, run the following code

import sys
from PyQt5.QtCore import *
from PyQt5.QtGui import *
from PyQt5.QtWidgets import *
def window():
   app = QApplication(sys.argv)
   w = QWidget()
   b = QLabel(w)
   b.setText("Hello World!")
   w.setGeometry(100,100,200,50)
   b.move(50,20)
   w.setWindowTitle("PyQt5")
   w.show()
   sys.exit(app.exec_())
if __name__ == '__main__':
   window()

On execution in the IPython Shell I get the following error:

 File "/usr/lib/python3.9/site-packages/spyder_kernels/customize/spydercustomize.py", line 160, in __init__
    super(SpyderQApplication, self).__init__(*args, **kwargs)

TypeError: super(type, obj): obj must be an instance or subtype of type

The same code runs on a terminal using the standard python interpreter without problems.

Solution:

The error can be fixed by changing line 160 of spydercustomize.py from
super(SpyderQApplication, self).init(*args, **kwargs)
to
super().init(*args, **kwargs).

[impact27]

That is strange. Maybe you have several versions of PyQt5 installed? Unfortunately we can't use super() because of python 2