RuntimeError: the PyQt4.QtCore and PyQt5.QtCore modules both wrap the QObject class

[Osndok]

Qubes OS version
Qubes release 4.0 (R4.0)

Affected component(s) or functionality
qubes-qube-manager
qubes-template-manager

Brief summary
Installing an app that depends on python3-qt5 breaks the qube-manager & template-manager launch scripts.

To Reproduce
Steps to reproduce the behavior:

1. Open a dom0 terminal
2. Execute: sudo qubes-dom0-update python3-qt5
3. Execute: qubes-qube-manager
4. See error (copied below)

Expected behavior
Installing other tools into dom0 should not break qubes tools.

Actual behavior
Installing python-based qt5 tools breaks at least two qubes apps.

Screenshots

[user@dom0 ~]$ qubes-qube-manager 
Traceback (most recent call last):
  File "/usr/bin/qubes-qube-manager", line 9, in <module>
    load_entry_point('qubesmanager==4.0.41', 'console_scripts', 'qubes-qube-manager')()
  File "/usr/lib/python3.5/site-packages/pkg_resources/__init__.py", line 542, in load_entry_point
    return get_distribution(dist).load_entry_point(group, name)
  File "/usr/lib/python3.5/site-packages/pkg_resources/__init__.py", line 2575, in load_entry_point
    return ep.load()
  File "/usr/lib/python3.5/site-packages/pkg_resources/__init__.py", line 2235, in load
    return self.resolve()
  File "/usr/lib/python3.5/site-packages/pkg_resources/__init__.py", line 2241, in resolve
    module = __import__(self.module_name, fromlist=['__name__'], level=0)
  File "/usr/lib/python3.5/site-packages/qubesmanager/qube_manager.py", line 40, in <module>
    from PyQt4 import QtGui  # pylint: disable=import-error
RuntimeError: the PyQt4.QtCore and PyQt5.QtCore modules both wrap the QObject class

Additional context
The python3-qt5 package brings in about 80mb of dependencies, but I'm pretty sure that it is the one that is actually disrupting the qubes apps.

Solutions you've tried
Executing sudo dnf remove python3-qt5 can be used to temporarily workaround the issue. I suspect that one could use a harsher rpm command to remove only that package without dependencies to get the same effect (while leaving the system in an inconsistent state).

Relevant documentation you've consulted
I have not consulted any Qubes documentation about this issue.

Related, non-duplicate issues

Other qt5 issue?

• Missing labels in Qt5 qubesmanager #5354
• Error in GUI Backup in Qt5 #5348
• R4.1: qubes-manager on Qt5 has all the colums the same width, instead of fitted to the content #5278

[marmarek]

AFAIR quamash module loads qt5 when available, but qubes manager in R4.0 uses qt4. There was a method to force specific version, @marmarta do you remember how? Can you put that into qubes manager code (into release4.0 branch)? I assume it applies to all applications in qubes-manager repository (all are pyqt based).

[marmarek]

Fixed in QubesOS/qubes-manager#237

[qubesos-bot]

Automated announcement from builder-github

The package qubes-manager-4.0.42-1.fc25 has been pushed to the r4.0 testing repository for dom0.
To test this update, please install it with the following command:

sudo qubes-dom0-update --enablerepo=qubes-dom0-current-testing

Changes included in this update

[qubesos-bot]

Automated announcement from builder-github

The package qubes-manager-4.0.42-1.fc25 has been pushed to the r4.0 stable repository for dom0.
To install this update, please use the standard update command:

sudo qubes-dom0-update

Or update dom0 via Qubes Manager.

Changes included in this update