大家好，大概两年前我尝试更新Python时搞砸了，现在想升级我的Ubuntu发行版，结果遇到一堆问题。我不常用这个笔记本，对Linux也不太熟悉，查了不少论坛但都没解决问题。我收集了一些信息，希望能帮大家准确理解我的问题——看起来可能是环境变量丢了，而且我装了好几个Python版本，之前还试过设置别名，但显然搞坏了什么，现在终端命令用不了，发行版也升级不了。

一、当前系统版本信息 #

NAME="Ubuntu"
VERSION="18.04.6 LTS (Bionic Beaver)"
ID=ubuntu
ID_LIKE=debian
PRETTY_NAME="Ubuntu 18.04.6 LTS"
VERSION_ID="18.04"
HOME_URL="https://www.ubuntu.com/"
SUPPORT_URL="https://help.ubuntu.com/"
BUG_REPORT_URL="https://bugs.launchpad.net/ubuntu/"
PRIVACY_POLICY_URL="https://www.ubuntu.com/legal/terms-and-policies/privacy-policy"
VERSION_CODENAME=bionic
UBUNTU_CODENAME=bionic

二、核心问题表现 #

• 执行python、python3、xterm等命令时，均返回Command not found
• 尝试升级发行版时，APT报错，无法完成更新

三、升级时的APT错误日志（/var/log/apt/term.log） #

Log started: 2023-08-28  12:04:52

(Reading database ...
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y(Reading database ... 90%
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(Reading database ... 100%
(Reading database ... 614694 files and directories currently installed.)

Preparing to unpack .../0-python3-apt_1.6.6_amd64.deb ...
/var/lib/dpkg/info/python3-apt.prerm: 6: /var/lib/dpkg/info/python3-apt.prerm: py3clean: not found
dpkg: warning: old python3-apt package pre-removal script subprocess returned error exit status 127
dpkg: trying script from the new package instead ...
/var/lib/dpkg/tmp.ci/prerm: 6: /var/lib/dpkg/tmp.ci/prerm: py3clean: not found
dpkg: error processing archive /tmp/apt-dpkg-install-awgn7N/0-python3-apt_1.6.6_amd64.deb (--unpack):
new python3-apt package pre-removal script subprocess returned error exit status 127
/var/lib/dpkg/info/python3-apt.postinst: 6: /var/lib/dpkg/info/python3-apt.postinst: py3compile: not found
dpkg: error while cleaning up:
installed python3-apt package post-installation script subprocess returned error exit status 127

Preparing to unpack .../1-python3-mako_1.0.7+ds1-1ubuntu0.2_all.deb ...
/var/lib/dpkg/info/python3-mako.prerm: 6: /var/lib/dpkg/info/python3-mako.prerm: py3clean: not found
dpkg: warning: old python3-mako package pre-removal script subprocess returned error exit status 127
dpkg: trying script from the new package instead ...
/var/lib/dpkg/tmp.ci/prerm: 6: /var/lib/dpkg/tmp.ci/prerm: py3clean: not found
dpkg: error processing archive /tmp/apt-dpkg-install-awgn7N/1-python3-mako_1.0.7+ds1-1ubuntu0.2_all.deb (--unpack):
new python3-mako package pre-removal script subprocess returned error exit status 127
/var/lib/dpkg/info/python3-mako.postinst: 6: /var/lib/dpkg/info/python3-mako.postinst: py3compile: not found
dpkg: error while cleaning up:
installed python3-mako package post-installation script subprocess returned error exit status 127

Preparing to unpack .../2-python3-pil_5.1.0-1ubuntu0.8_amd64.deb ...
/var/lib/dpkg/info/python3-pil:amd64.prerm: 6: /var/lib/dpkg/info/python3-pil:amd64.prerm: py3clean: not found
dpkg: warning: old python3-pil:amd64 package pre-removal script subprocess returned error exit status 127
dpkg: trying script from the new package instead ...
/var/lib/dpkg/tmp.ci/prerm: 6: /var/lib/dpkg/tmp.ci/prerm: py3clean: not found
dpkg: error processing archive /tmp/apt-dpkg-install-awgn7N/2-python3-pil_5.1.0-1ubuntu0.8_amd64.deb (--unpack):
new python3-pil:amd64 package pre-removal script subprocess returned error exit status 127
/var/lib/dpkg/info/python3-pil:amd64.postinst: 6: /var/lib/dpkg/info/python3-pil:amd64.postinst: py3compile: not found
dpkg: error while cleaning up:
installed python3-pil:amd64 package post-installation script subprocess returned error exit status 127

Preparing to unpack .../3-python3-pkg-resources_39.0.1-2ubuntu0.1_all.deb ...
/var/lib/dpkg/info/python3-pkg-resources.prerm: 6: /var/lib/dpkg/info/python3-pkg-resources.prerm: py3clean: not found
dpkg: warning: old python3-pkg-resources package pre-removal script subprocess returned error exit status 127
dpkg: trying script from the new package instead ...
/var/lib/dpkg/tmp.ci/prerm: 6: /var/lib/dpkg/tmp.ci/prerm: py3clean: not found
dpkg: error processing archive /tmp/apt-dpkg-install-awgn7N/3-python3-pkg-resources_39.0.1-2ubuntu0.1_all.deb (--unpack):
new python3-pkg-resources package pre-removal script subprocess returned error exit status 127
/var/lib/dpkg/info/python3-pkg-resources.postinst: 6: /var/lib/dpkg/info/python3-pkg-resources.postinst: py3compile: not found
dpkg: error while cleaning up:
installed python3-pkg-resources package post-installation script subprocess returned error exit status 127

y

Preparing to unpack .../4-python3-problem-report_2.20.9-0ubuntu7.29_all.deb ...
/var/lib/dpkg/info/python3-problem-report.prerm: 6: /var/lib/dpkg/info/python3-problem-report.prerm: py3clean: not found
dpkg: warning: old python3-problem-report package pre-removal script subprocess returned error exit status 127
dpkg: trying script from the new package instead ...
/var/lib/dpkg/tmp.ci/prerm: 6: /var/lib/dpkg/tmp.ci/prerm: py3clean: not found
dpkg: error processing archive /tmp/apt-dpkg-install-awgn7N/4-python3-problem-report_2.20.9-0ubuntu7.29_all.deb (--unpack):
new python3-problem-report package pre-removal script subprocess returned error exit status 127
/var/lib/dpkg/info/python3-problem-report.postinst: 6: /var/lib/dpkg/info/python3-problem-report.postinst: py3compile: not found
dpkg: error while cleaning up:
installed python3-problem-report package post-installation script subprocess returned error exit status 127

Preparing to unpack .../5-python3-protobuf_3.0.0-9.1ubuntu1.1_amd64.deb ...
/var/lib/dpkg/info/python3-protobuf.prerm: 6: /var/lib/dpkg/info/python3-protobuf.prerm: py3clean: not found
dpkg: warning: old python3-protobuf package pre-removal script subprocess returned error exit status 127
dpkg: trying script from the new package instead ...
/var/lib/dpkg/tmp.ci/prerm: 6: /var/lib/dpkg/tmp.ci/prerm: py3clean: not found
dpkg: error processing archive /tmp/apt-dpkg-install-awgn7N/5-python3-protobuf_3.0.0-9.1ubuntu1.1_amd64.deb (--unpack):
new python3-protobuf package pre-removal script subprocess returned error exit status 127
/var/lib/dpkg/info/python3-protobuf.postinst: 6: /var/lib/dpkg/info/python3-protobuf.postinst: py3compile: not found
dpkg: error while cleaning up:
installed python3-protobuf package post-installation script subprocess returned error exit status 127

Preparing to unpack .../6-python3-uno_1%3a6.0.7-0ubuntu0.18.04.13_amd64.deb ...
/var/lib/dpkg/info/python3-uno.prerm: 6: /var/lib/dpkg/info/python3-uno.prerm: py3clean: not found
dpkg: warning: old python3-uno package pre-removal script subprocess returned error exit status 127
dpkg: trying script from the new package instead ...
/var/lib/dpkg/tmp.ci/prerm: 6: /var/lib/dpkg/tmp.ci/prerm: py3clean: not found
dpkg: error processing archive /tmp/apt-dpkg-install-awgn7N/6-python3-uno_1%3a6.0.7-0ubuntu0.18.04.13_amd64.deb (--unpack):
new python3-uno package pre-removal script subprocess returned error exit status 127
/var/lib/dpkg/info/python3-uno.postinst: 6: /var/lib/dpkg/info/python3-uno.postinst: py3compile: not found
dpkg: error while cleaning up:
installed python3-uno package post-installation script subprocess returned error exit status 127

Preparing to unpack .../7-python3-louis_3.5.0-1ubuntu0.5_all.deb ...
/var/lib/dpkg/info/python3-louis.prerm: 6: /var/lib/dpkg/info/python3-louis.prerm: py3clean: not found
dpkg: warning: old python3-louis package pre-removal script subprocess returned error exit status 127
dpkg: trying script from the new package instead ...
/var/lib/dpkg/tmp.ci/prerm: 6: /var/lib/dpkg/tmp.ci/prerm: py3clean: not found
dpkg: error processing archive /tmp/apt-dpkg-install-awgn7N/7-python3-louis_3.5.0-1ubuntu0.5_all.deb (--unpack):
new python3-louis package pre-removal script subprocess returned error exit status 127
/var/lib/dpkg/info/python3-louis.postinst: 6: /var/lib/dpkg/info/python3-louis.postinst: py3compile: not found
dpkg: error while cleaning up:
installed python3-louis package post-installation script subprocess returned error exit status 127

Errors were encountered while processing:
/tmp/apt-dpkg-install-awgn7N/0-python3-apt_1.6.6_amd64.deb
/tmp/apt-dpkg-install-awgn7N/1-python3-mako_1.0.7+ds1-1ubuntu0.2_all.deb
/tmp/apt-dpkg-install-awgn7N/2-python3-pil_5.1.0-1ubuntu0.8_amd64.deb
/tmp/apt-dpkg-install-awgn7N/3-python3-pkg-resources_39.0.1-2ubuntu0.1_all.deb
/tmp/apt-dpkg-install-awgn7N/4-python3-problem-report_2.20.9-0ubuntu7.29_all.deb
/tmp/apt-dpkg-install-awgn7N/5-python3-protobuf_3.0.0-9.1ubuntu1.1_amd64.deb
/tmp/apt-dpkg-install-awgn7N/6-python3-uno_1%3a6.0.7-0ubuntu0.18.04.13_amd64.deb
/tmp/apt-dpkg-install-awgn7N/7-python3-louis_3.5.0-1ubuntu0.5_all.deb

Log ended: 2023-08-28  12:04:56

四、导致问题的历史操作记录（history相关片段） #

172  sudo apt install ruby-full
173  ruby --version\
174  ruby --version
175  ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"
176  sudo apt-get install build-essential
177  brew install gcc
178  echo 'eval "$(/home/linuxbrew/.linuxbrew/bin/brew shellenv)"' >> /home/brittany/.profile
179  eval "$(/home/linuxbrew/.linuxbrew/bin/brew shellenv)"
180  brew install gcc
181  brew install sdl sdl_mixer sdl_sound sdl_tff
182  brew install sdl sdl_mixer sdl_sound sdl_ttf
183  pip3 install pygame
184  pip3 install pgzero
185  gedit ~/.bashrc export PATH=/home/brittany/.local/bin/:$PATH
186  gedit~/.bashrc export PATH=/home/brittany/.local/bin/:$PATH
187  gedit~/.bashrc
188  gedit ~/.bashrc
189  source ~/.bashrc
190  idel3
191  idel
192  idle
193  sudo apt update
194  python3
195  python3 --version
196  sudo add-apt-repository ppa:deadsnakes/ppa
197  sudo apt update
198  python3 --version
199  apt list | grep python3.10
200  sudo apt install python3
201  python3 --version
202  sudo apt install software-properties-common
203  sudo apt --only-upgrade install python3
204  sudo apt install python3.10
205  python3 --version
206  sudo nano /usr/bin/gnome-terminal
207  sudo update-alternatives --install /usr/bin/python3 python3 /usr/bin/python3.9 1
208  sudo update-alternatives --install /usr/bin/python3 python3 /usr/bin/python3.10 2
209  sudo update-alternatives --config python3
210  python3 --version
211  pip
212  sudo apt remove --purge python3-apt
213  sudo apt autoclean
214  sudo apt install python3-apt
215  pip
216  sudo apt install python3.10-distutils
217  curl https://bootstrap.pypa.io/get-pip.py -o get-pip.py
218  sudo python3.10 get-pip.py
219  sudo apt install curl
220  curl https://bootstrap.pypa.io/get-pip.py -o get-pip.py
221  sudo python3.10 get-pip.py [B
222  IDLE
223  python
224  python3
225  idle3.10
226  idle3
227  sudo apt install idle
228  sudo apt install idle3
229  idle3
230  idle
231  idle3
232  python3
233  idle
234  idle3
235  dpkg -L idle3
236  sudo apt-get install idle-python3.10

五、已安装的Python版本 #

执行ls /usr/bin/python*的输出：

/usr/bin/python
/usr/bin/python3
/usr/bin/python3.10
/usr/bin/python3.6
/usr/bin/python3.6m
/usr/bin/python3m

六、当前PATH环境变量 #

执行echo $PATH的输出：

/home/linuxbrew/.linuxbrew/bin:/home/linuxbrew/.linuxbrew/sbin:/home/brittany/.local/bin