ImportError：无法从“PyQt5.QtGui”导入名称“QColorConstants”

Question

i have Ubuntu 20.04.4 LTS python 3.8.10 64bits and i have this error: Traceback (most recent call last): File "", line 6, in ImportError: cannot import name 'QColorConstants' from 'PyQt5.QtGui' (/usr/lib/python3/dist-packages/PyQt5/QtGui.abi3.so)

i found this in order to update pyqt from 5.14: https://askubuntu.com/questions/1383590/is-it-possible-to-install-python3-pyqt5-5-15-on-ubuntu-20-04

But still it doesn't work

>>> from PyQt5.QtCore import PYQT_VERSION_STR
>>> PYQT_VERSION_STR
'5.15.2'

Answer 1

I ran these commands (the typical one) in a virtual environment of python 3.8.10 in Ubuntu 20.04.4:

pip install pyqt5

And it installed version 5.15.6 . I recommend to uninstall your package first with

pip uninstall pyqt5

and then the pip install command. Alternatively. if you want a specific version of the package (I assume 5.15.5) you can just force it during the installation with

pip install pyqt5==5.15.5

Anyway, with version 5.15.6 I can do your import.

However, I got your error

ImportError: cannot import name 'QColorConstants' from 'PyQt5.QtGui.py"
Traceback (most recent call last):
  File "path-here" - ImportError: cannot import name 'QColorConstants' from 'PyQt5.QtGui.py", line 2, in <module>
    from pyqt5.QtCore import PYQT_VERSION_STR
ModuleNotFoundError: No module named 'pyqt5'

when I tried

from pyqt5.QtCore import PYQT_VERSION_STR

print(PYQT_VERSION_STR)

instead of

from PyQt5.QtCore import PYQT_VERSION_STR

print(PYQT_VERSION_STR)

which gives the correct output. Check if you import somewhere pyqt5 instead of PyQt5 .