qt5 no module named '_hal'

When starting qt5 in a terminal, there are no linuxcnc widgets and after closing qt5, there is following error:
...
File "/usr/lib/python2.7/dist-packages/hal.py, line 30, in <module>
ModuleNotFoundError: No modules named '_hal'

A file '_hal.py' didn't exist and i don't know why. How can i eleminate this error?

Seems to be a python version problem.
What version of linuxcnc are you using?

It is LinuxCNC V2.8.4 .

what do you see in the folder:
/usr/lib/x86_64-linux-gnu/qt5/plugins/designer

sorry, the i try to send the image as attachment.

Ok the file libpyqt5.so is most likely the python3 version, you need the python2 version.
you need to find out the qt version you are using, if you open designer and look in ABOUT qt, it should tell you - something like 5.7.1 version.

This is the readme that explains the problem:
github.com/LinuxCNC/linuxcnc/blob/2.8/li.../designer/README.txt

There is a file 'install_script' that can be run to automate the changes:
It should be here on your system:
/usr/lib/python2.7/dist-packages/qtvcp/designer/install_script

Thank you. Unfortunately i could not find the libraries descripted in the readme file, just as the "install-script" in the folder, you told me.
Where can i get from, respectively is it necessary to install something else?
The qt5 designer i had installed, as described in the readme file.
 

Are you using an installed version of linuxcnc or a compiled version?
Which files are missing?
Did you find the script?
Is there a folder here: /usr/lib/python2.7/dist-packages/qtvcp/ ?

It was a .ISO with 2.8.2 and later updated to 2.8.4.
The folder "/usr/lib/python2.7/dist-packages/qtvcp" exists with:
cnc@LinuxCNC:/usr/lib/python2.7/dist-packages/qtvcp$ 
core.py
logger.py
qt_istat.pyc
qt_pstat.pyc  
test1.ui
core.pyc    
logger.pyc  
qt_makegui.py  
qt_tstat.py  
widgets
designer  
plugins    
qt_makegui.pyc
qt_tstat.pyc
__init__.py
qt_action.py  
qt_makepins.py
qtvcp_handler.py
__init__.pyc
qt_action.pyc
qt_makepins.pyc
qtvcp_handler.pyc
lib    
qt_istat.py  
qt_pstat.py
README.txt

The folder "/usr/lib/python2.7/dist-packages/qtvcp/designer" exists too with:
README.txt
x86_64

Is it necessary to install or download something else?

Here is the script:
github.com/LinuxCNC/linuxcnc/blob/2.8/li...igner/install_script
should go in /usr/lib/python2.7/dist-packages/qtvcp/designer
and run from there.