Unable to use fitz with python 3.8

I use pymupdf to automatically sign my document. But the package name is pymupdf even the warning is that “fitz”  is not installed. If come across an error message like import fitz File “/home/phsamuel/p3/lib/python3.10/site-packages/fitz/__init__.py”, line 1, in <module> from frontend import * File “/home/phsamuel/p3/lib/python3.10/site-packages/frontend/__init__.py”, line 1, in <module> from .events import * File “/home/phsamuel/p3/lib/python3.10/site-packages/frontend/events/__init__.py”, line…