PyQt5 version 5.11.2 ImportError: undefined symbol: PySlice_AdjustIndices

[Matthias Homann]

Using latest installation script on Ubuntu 16.04 installs PyQt5 version 5.11.2, but this seems to lack the function PySlice_AdjustIndices.

$ rapid-photo-downloader
Traceback (most recent call last):
  File "/home/matthias/bin/rapid-photo-downloader", line 7, in <module>
    from raphodo.rapid import main
  File "/home/matthias/bin/rpd/lib/python3.5/site-packages/raphodo/rapid.py", line 75, in <module>
    from PyQt5 import QtCore
ImportError: /home/matthias/bin/rpd/lib/python3.5/site-packages/PyQt5/QtCore.so: undefined symbol: PySlice_AdjustIndices

As a workaround I downgraded PyQt5 to version 5.9.1 (found the hint in this discussion: https://riverbankcomputing.com/pipermail/pyqt/2018-July/040518.html)

$ pip install pyqt5==5.9.1