Ubuntu 20.04升级到22.04.2后Python与pip版本及程序调用问题求助

我刚把Ubuntu 20.04升级到22.04，现在遇到了Python版本相关的一堆问题。之前20.04里我只有Python 3.8，升级后系统里好像只剩Python 3.10了。

先贴一下我查Python可执行文件的终端输出：

(base) giammi56@giammi56-T440p:~$ ls /usr/bin/python*

/usr/bin/python
/usr/bin/python3.10-config
/usr/bin/python3-pasteurize
/usr/bin/python3
/usr/bin/python3-config
/usr/bin/python-argcomplete-check-easy-install-script3
/usr/bin/python3.10
/usr/bin/python3-futurize
/usr/bin/python-argcomplete-tcsh3

用apt查Python3.8的情况，显示是残留配置：

(base) giammi56@giammi56-T440p:~$ apt list | grep python3.8

WARNING: apt does not have a stable CLI interface. Use with caution in scripts.

libpython3.8-minimal/now 3.8.10-0ubuntu1~20.04.6 amd64 [residual-config]
python3.8-minimal/now 3.8.10-0ubuntu1~20.04.6 amd64 [residual-config]

另外，在20.04的时候我把pip别名成了pip3，现在这个设置会不会出问题？我查了几个pip版本的信息：

(base) giammi56@giammi56-T440p:~$ pip --version

pip 23.0.1 from /home/giammi56/.local/lib/python3.10/site-packages/pip (python 3.10)

(base) giammi56@giammi56-T440p:~$ pip3 --version

pip 23.0.1 from /home/giammi56/.local/lib/python3.10/site-packages/pip (python 3.10)

(base) giammi56@giammi56-T440p:~$ pip3.8 --version
pip 23.0.1 from /home/giammi56/.local/lib/python3.10/site-packages/pip (python 3.10)

现在更头疼的是，有些用pip装的程序没法正常工作，Undervolt就是个典型例子——普通用户身份能识别命令，但用sudo就找不到：

(base) giammi56@giammi56-T440p:~$ sudo undervolt --read

sudo: undervolt: command not found

(base) giammi56@giammi56-T440p:~$ undervolt

usage: undervolt [-h] [--version] [-v] [-f] [-r] [-t TEMP] [--temp-bat TEMP_BAT] [--throttlestop THROTTLESTOP]
[...]

我用locate找了Undervolt的位置，能看到它装在Python3.8的目录里：

(base) giammi56@giammi56-T440p:~$ locate undervolt

/etc/systemd/system/undervolt.service
/etc/systemd/system/hibernate.target.wants/undervolt.service
/etc/systemd/system/hybrid-sleep.target.wants/undervolt.service
/etc/systemd/system/multi-user.target.wants/undervolt.service
/etc/systemd/system/suspend.target.wants/undervolt.service
/home/giammi56/.cache/pip/wheels/ad/e5/e3/b8b0b993874dde746b5d3ffc16b122f15045fb98abd12d41ab/undervolt-0.3.0-py3-none-any.whl
/home/giammi56/.local/bin/undervolt
/home/giammi56/.local/lib/python3.8/site-packages/undervolt-0.3.0.dist-info
/home/giammi56/.local/lib/python3.8/site-packages/undervolt.py
/home/giammi56/.local/lib/python3.8/site-packages/__pycache__/undervolt.cpython-38.pyc
/home/giammi56/.local/lib/python3.8/site-packages/undervolt-0.3.0.dist-info/INSTALLER
/home/giammi56/.local/lib/python3.8/site-packages/undervolt-0.3.0.dist-info/METADATA
/home/giammi56/.local/lib/python3.8/site-packages/undervolt-0.3.0.dist-info/RECORD
/home/giammi56/.local/lib/python3.8/site-packages/undervolt-0.3.0.dist-info/REQUESTED
/home/giammi56/.local/lib/python3.8/site-packages/undervolt-0.3.0.dist-info/WHEEL
/home/giammi56/.local/lib/python3.8/site-packages/undervolt-0.3.0.dist-info/entry_points.txt
/home/giammi56/.local/lib/python3.8/site-packages/undervolt-0.3.0.dist-info/top_level.txt
/usr/local/bin/undervolt
/usr/local/lib/python3.8/dist-packages/undervolt-0.3.0.dist-info
/usr/local/lib/python3.8/dist-packages/undervolt.py
/usr/local/lib/python3.8/dist-packages/__pycache__/undervolt.cpython-38.pyc
/usr/local/lib/python3.8/dist-packages/undervolt-0.3.0.dist-info/INSTALLER
/usr/local/lib/python3.8/dist-packages/undervolt-0.3.0.dist-info/METADATA
/usr/local/lib/python3.8/dist-packages/undervolt-0.3.0.dist-info/RECORD
/usr/local/lib/python3.8/dist-packages/undervolt-0.3.0.dist-info/WHEEL
/usr/local/lib/python3.8/dist-packages/undervolt-0.3.0.dist-info/entry_points.txt
/usr/local/lib/python3.8/dist-packages/undervolt-0.3.0.dist-info/top_level.txt

我现在完全不知道该怎么处理了。看到有帖子说可以通用重装，但我要不要把所有Python3.8的程序都升级到3.10版本呢？之前设置的pip别名还能用吗？如果我同时有多个Python版本，该怎么在终端、桌面文件或者service里调用对应版本的程序啊？真心求各位大佬帮忙！

备注：内容来源于stack exchange，提问作者giammi56