ModuleNotFoundError: No module named 'PyQt5'

[hydrowarrior4]

the full error message is:
File "/home/hydro/binary-waterfall/src/binary_waterfall/core.py", line 3, in <module>
from PyQt5.QtCore import Qt
ModuleNotFoundError: No module named 'PyQt5'
it shows this even though i installed pyqt5 so what's the issue?

[argho7]

How did you install it?
And your os/platform?