WSL2 - How do I uninstall other, accidentally installed versions of python(3)? - python

I installed a bunch of python versions from a bunch of different sources while trying to upgrade from python3.8 to python3.11 on WSL2 and now I have no idea:
which ones of the installed versions I can delete (since they were wrongly installed and are not used)
how I can delete them
which one is the one I am using now as python3.11 (since I would want to keep just that one)
and which one is the system default python that should never be deleted.
In the following I'm first going to explain how I got to the point that I am at now and then explain the specific details of the problem that I'm facing trying to delete the correct versions (as in the versions that I dont need anymore) in the TLDR section.
I was trying to upgrade my version of python3 in WSL2 from 3.8 to 3.11. I tried a few guides to install python3.11.
First I followed this one which installs python3.11 using sudo add-apt-repository ppa:deadsnakes/ppa , sudo apt install python3.11 and sudo apt update.
It then proceeds to set the default python version using sudo apt update-alternatives and a few other commands. This didn't work for me however, since WSL2 said that there were no update-alternatives.
When I executed python3 --version it still said that I have python3.8.
Therefore I then proceeded to follow this guide which uses:
$ tar xvf Python-3.11.tgz
$ cd Python-3.11
$ ./configure --enable-optimizations --with-ensurepip=install
$ make -j 8
$ sudo make altinstall
After installation however python3 --version still showed python3.8. Then I found this guide to change my system to use python3.11 using symbolic links. Now it works and python3 --version shows python3.11 and my system uses it.
TLDR: Now on to my problem of not knowing which versions to delete and how to delete them properly / thorougly / without breaking anything:
which python3 shows /usr/bin/python3 and which python3.11 shows /usr/local/bin/python3.11. My /usr/bin/ and my /bin/ folder folder look like this now and my /usr/local/bin/ folder looks like this.
I honestly am so confused even, as to what folder is what, as navigating like this:
$ cd ~
$ cd /
$ cd home/myusername/
leads me back to being at ~ and inside the / folder there is the bin/ folder containing all this stuff but then inside /usr/local/bin/ there is all this stuff again. Then in /home/myusername/ there is nothing even though there should be a bin folder too according to most websites. Instead it leads me back to ~.
So any help would be much appreciated in figuring out which of those python versions I can delete now, how I do this and what all the confusion with the directories means.
Thanks in advance!

Related

env: python: No such file or directory when building app with Xcode

When I build/run/archive my app in Xcode (on MacOS 12.3) I encounter this error:
env: python: No such file or directory
Command Ld failed with a nonzero exit code
I think I might have changed something with regard to my python environment while working on a school project or messed something up there. However, I can not figure out what is wrong.
I tried reinstalling Xcode and python (using brew and pyenv). I also relinked python using brew. But I still encounter the same error.
Which python gives the following results:
which python3
-> /usr/local/bin/python3
And in my ~/.zshrc I have the following line:
export PATH=/usr/local/bin:/usr/local/sbin:~/bin:$PATH
Any help would be appreciated! If I missed or forgot anything please let me know, I'm quite new to this.
Homebrew only installs the binary python3, just to be safe. Xcode is complaining about a lack of the binary python (note the lack of a 3!).
You have a couple of options:
When installing python3, Homebrew also creates a libexec folder with unversioned symlinks, such as python (what you're missing). Note the Caveats printed when installing it:
$ brew info python
python#3.9: stable 3.9.10 (bottled)
==> Caveats
Python has been installed as
/opt/homebrew/bin/python3
Unversioned symlinks `python`, `python-config`, `pip` etc. pointing to
`python3`, `python3-config`, `pip3` etc., respectively, have been installed into
/opt/homebrew/opt/python#3.9/libexec/bin
See: https://docs.brew.sh/Homebrew-and-Python
You could add this directory to your $PATH, such that python and pip become available; something like the following might suffice:
echo 'export PATH="'"$(brew --prefix)"'/opt/python#3.9/libexec/bin:$PATH"' \
>>~/.bash_profile
... although that will need to be modified according to your precise version of Python3, your shell of choice, etc.
Alternatively and more simply, although a little more jankily, you could simply manually create the appropriate symlinks:
ln -s "$(brew --prefix)/bin/python"{3,}
I had posted the same question on nativescript official github and the solution that worked for me was in the answer by the user shilik
Monterey 12.3 removes python 2. All you need to do is to reinstall
python2 back to system from this link
https://www.python.org/downloads/release/python-2718/
install python3
run 'ln -s /usr/bin/python3 /usr/local/bin/python',Create a link to Python
Add -f to be effective.
ln -s -f /usr/local/bin/python3 /usr/local/bin/python
For me the problem was with missing python
env: python: No such file or directory
BUT in the end missing was python version 2.x after updating to macOS Monterey 12.5 (21G72).
Problem was resolved by installing python from:
https://www.python.org/downloads/release/python-2718/
What I've also tried but you probably don't have to do:
sudo brew install python
sudo brew upgrade
sudo ln -s -f /usr/local/bin/python3 /usr/local/bin/python
sudo ln -s $(which python3) /usr/local/bin/python
sudo ln -s $(which python3) /Applications/Xcode.app/Contents/Developer/usr/bin/python
sudo ln -s /Applications/Xcode.app/Contents/Developer/usr/bin/python3 /Applications/Xcode.app/Contents/Developer/usr/bin/python
This took me days of head scratching, and none of the solutions I found on the internet worked.
Eventually what DID work for me was this:
sudo ln -s /Applications/Xcode.app/Contents/Developer/usr/bin/python3 /Applications/Xcode.app/Contents/Developer/usr/bin/python
I used the find command to find all instances of python in the file hierarchy:
find / -name python*
and I saw that there was a symbolic link labelled python3 in /Applications/Xcode.app/Contents/Developer/usr/bin/ that was linked to a python instance deep within the bowels of Xcode.
However there was no symbolic link labelled python which seems to be what Xcode is looking for.
So I created a symbolic link linking python to python3 and that did the trick.
For what it's worth, I installed python via pyenv which I installed through homebrew on a 2020 Mac mini M1.
In my case, created symbolic link for dev_appserver.py like below.
ln -s /opt/local/bin/python2.7 /usr/local/bin/python
ln -s /opt/local/bin/python2.7 /usr/local/bin/python2
Command location and version should be adapted to your environment.
I was able to solve this issue with the above-mentioned answers.
In my case, while I was trying npm install in my node project and was facing this issue.
Note: % brew install python is a prerequisite for all the below steps! Test if python is correctly installed by brew python info
First thing which comes to mind is if python is correctly installed and the path is set correctly.
python --version was giving zsh - python not found error while python3 --version was a success.
Next steps were to set the correct path. I did the below steps and it worked:
echo "alias python=/usr/bin/python3" >> ~/.zshrc
ln -s -f "$(brew --prefix)/bin/python"{3,}
ln -s -f "$(which python3)"{3,}
What I was missing was to run brew install python, and it worked like a charm!

Can't find Python when building Qt from sources

We are trying to build the last version of Qt ( qt-15.5.0 ) from the sources on Ubuntu 20.04. Everything is running fine until we get the following error:
Project ERROR: Building QtQml requires Python.
Python is avalaible ( version 3.8 ), we even tried alias python=python3 and adding the path to python to $PATH but it didn't help. We can't find any info on this specific problem.
What we did:
$ wget http://download.qt.io/official_releases/qt/5.15/5.15.0/single/qt-everywhere-src-5.15.0.tar.xz
$ ./configure -prefix /username/dev/libraries/qt-5.15.0/install -xcb
$ make -j8
$ sudo make install
Whilst manually setting the alias is a quick workaround, and it helps in many cases, this solution is less useful when dealing with systems that are managed in an automated fashion.
In order to come around this issue, in Ubuntu 22 at least there is a meta-package available, which solves the issue:
sudo apt install python-is-python3
Other distros may possibly have similar solutions readily available.
$ vi .bashrc
Add the following alias to the .bashrc file.
alias python=python3
Save it and source the script.
$ source .bashrc
If it didn't work, use
$ which python3
/usr/bin/python3
$ sudo cp /usr/bin/python3 /usr/bin/python
Then you are ready to build your Qt!

Installing python from download in Ubuntu 19.10

My default version of python3 is 3.7.5. I need to install 3.6.5. I was told that ubuntu 19.10 depends on 3.7.5. So I cannot replace it. I need them to be side by side. I have ran these lines on the command prompt:
wget -P ~/Downloads https://www.python.org/ftp/python/3.6.5/Python-3.6.5.tar.xz
cd ~/Downloads
tar -xJf Python-3.6.5.tar.xz
cd Python-3.6.5
./configure
make
make test
After the "make test" command is entered, some tests failed. And it has been running for hours.
The final line is either:
sudo make install
or
sudo make altinstall
I was told that the first option will replace 3.7.5, while the second will install them side by side.
Questions:
Since some tests failed, can I still install 3.6.5? What does it mean that the tests are failing.
is "sudo make altinstall" the right command to install them side by side? If so, what is the command to run 3.6.5, if 3.7.5 will still be the default?
How about using version manager?
Example.
pyenv
anaconda
virtualenv
It depends on what tests are failing. It could have been some packages which are currently not required/not being used. So yes, you can continue with the install and check.
Yes it is correct. The corresponding versions can be invoked by mentioning the absolute path until the python folder.
For example /usr/bin/python3.6.5 or /usr/bin/python3.7.5

How do I replace a Python installed from source with a packaged version?

As Python 3.7 was being prepared I installed Python 3.7.0b3 from source. Now 3.7 is out and I want to use the version packaged for Ubuntu. So I've done
apt-get install python3.7
but
$ which python3.7
/usr/local/bin/python3.7
$ /usr/local/bin/python3.7 --version
Python 3.7.0b3
How does one uninstall a Python installed from source (on Ubuntu)?
Or how can I replace it with the apt repo packaged version?
Since you opened a bounty, I can't vote to close as a duplicate, but this question would seem to provide a possible solution. Quoting from the accepted answer:
You can use checkinstall to remove Python. The idea is:
Install checkinstall
Use
checkinstall to make a deb of your
Python installation
Use dpkg -r to
remove the deb.
checkinstall basically wraps a make install command and creates a Debian .deb package based on what was installed. Then, you can just uninstall that package to reverse make install completely. To be perfectly safe you may want to uninstall the packaged Python 3.7 first and reinstall it afterwards to avoid any conflicts (I wouldn't expect any, though, since the packaged version lives in /usr while your source version lives in /usr/local).
If you don't have your source files around anymore, you can always download them again (https://www.python.org/downloads/release/python-370b3/) and rebuild Python. Specifically, the checkinstall commands would look something like this:
sudo apt install checkinstall
wget https://www.python.org/ftp/python/3.7.0/Python-3.7.0b3.tgz
tar xf Python-3.7.0b3.tgz
cd Python-3.7.0b3
./configure && make
sudo checkinstall -D --fstrans=no make install
sudo dpkg -r Python-3.7.0b3.deb
(-D creates a Debian package, --fstrans=no disables use of a temporary directory for installation).
Since I was also moving to python 3.7, I came across this question and decided to answer it, as well as finish my installation.
This are the two sources, which I used for installing python 3.7 on ubuntu 16.04:
https://askubuntu.com/questions/865554/how-do-i-install-python-3-6-using-apt-get
https://superuser.com/questions/241865/updating-python-on-ubuntu-system
Apparently from the first source the deadsnakes PPA contain Python 3.7 - Link: https://github.com/deadsnakes/python3.7/tree/ubuntu/xenial/Python
So following from my first source, I used the following commands to install Python 3.7:
sudo add-apt-repository ppa:deadsnakes/ppa
sudo apt-get update
sudo apt-get install python3.7
It installed Python 3.7 successfully but my Python 3.5.2 remains default. You can invoke/use Python 3.7 by running the commands:
python3.7 script.py
It works, so I decided to set Python 3.7 as default by removing python 3.5, but I came across my second source, and just decided to stick with using python3.7, when running my script in the terminal.
Apparently it says:
Ubuntu policies extensively for writing end-user software. So basically, a large part of the system is written in Python. To switch to Python 3.7, there needs to be done a piece of work consisting of updating and re-testing all the scripts.
So to say you can't just switch to Python 3.7 and delete the older version.
Also from a comment from my first source it states deleting the older version might break the system. I haven't been around to deleting my older version in case it might break the system, but since you are asking for how to download Python 3.7, I think my first source and the first part of my answer should to the work.
I hope it helps :)
It seems that your Python built from source is under /usr/local, and your PATH variable has /usr/local/bin before /usr/bin, since running python3.7 gets you the one under /usr/local rather than the packaged one which would be /usr/bin/python3.7.
Look at your PATH to verify this.
echo $PATH
(When you run a program in bash, that particular running bash instance will remember the location and not rescan the directories in the PATH for that program again, so it will not notice a new file that has appeared somewhere earlier in the PATH. You can prevent this by running hash -r to reset the cache or by just exiting the shell and launching it again.)
I presume your goal is for python3.7 (or any of the other commands provided by Python) to run the versions from your packaged install in /usr.
Unfortunately the python build process does not provide an uninstall method -- the only automated way to remove just the files installed by a source Python install requires using other tools ahead of time (such as checkinstall).
So you have some choices :
Change your PATH so that /usr/local/bin is after /usr/bin. To do this, edit your ~/.profile file or whatever other script you have configuring your PATH and logout/login. This will also affect any other commands you run that are available in both /usr/local/bin and /usr/bin.
Remove /usr/local and reinstall anything else you want there. If a Python install is the only thing in your /usr/local, or if you can easily reinstall anything else you had there, this might be the way to go.
Painstakingly figure out what files under /usr/local/bin were part of Python and remove them. You might be able use the corresponding files in /usr/bin from your installed python3 packages as a starting point to figure out the similar names for /usr/local/bin.
One-liner to get the list of files in /usr/bin from installed python3* packages:
$ for pkg in $(dpkg -l 'python3*' | grep '^ii' | cut -f 3 -d' '); do dpkg -L $pkg | grep '^/usr/bin/'; done | sort
This should produce a list of files like:
/usr/bin/2to3-3.x
/usr/bin/chardet3
...
(I've tested this one-liner on Debian, I'm not sure if any changes are required for Ubuntu)

python-dev installation error: ImportError: No module named apt_pkg

I am Debian user, and I want to install python-dev, but when I run the code in the shell as a root:
# aptitude install python-dev
I get the following error:
Traceback (most recent call last):
File "/usr/bin/apt-listchanges", line 28, in <module>
import apt_pkg
ImportError: No module named apt_pkg
What seems to be the problem and how can I resolve it?
I met this problem when doing sudo apt-get update. My env is debian8, with python2.7 + 3.4(default) + 3.5.
The following code will only re-create a apt_pkg....so file for python 3.5
sudo apt-get install python3-apt --reinstall
The following code solved my problem,
cd /usr/lib/python3/dist-packages
Locate the appropriate .so file for the python version installed on your system:
ls -l | grep apt_pkg
Create a symbolic link:
sudo ln -s apt_pkg.cpython-{your-version-number}-x86_64-linux-gnu.so apt_pkg.so
Replace {your-version-number} appropriately.
CAUTION, the following will create a symlink from apt_pkg37m to apt_pkg36m. make sure you are linking to the correct, or at least to an existing version by ls apt_pkg.cpython-*, and see which one(s) you have installed.
sudo ln -s apt_pkg.cpython-{36m,37m}-x86_64-linux-gnu.so
So, obviously, python3-apt checks the highest python version, instead of the current python version in use.
To understand why this is happening, see this answer further down: https://stackoverflow.com/a/64241654/21539
Solve it by this:
cd /usr/lib/python3/dist-packages
cp apt_pkg.cpython-34m-i386-linux-gnu.so apt_pkg.so
Or:
cd /usr/lib/python3/dist-packages
cp apt_pkg.cpython-35m-x86_64-linux-gnu.so apt_pkg.so
Basically, if you get a No such file or directory just ls to try to get the right name.
This happened to me on Ubuntu 18.04.2 after I tried to install Python3.7 from the deadsnakes repo.
Solution was this
1) cd /usr/lib/python3/dist-packages/
2) sudo ln -s apt_pkg.cpython-36m-x86_64-linux-gnu.so apt_pkg.so
Make sure you have a working python-apt package. You could try and remove and install that package again to fix the problem with apt_pkg.so not being located.
apt-get install python-apt
This error will often occur when a newer version of python has been installed alongside an older version e.g;
Ubuntu 18.04.1 ships with python version 3.6.6
Installed ppa:deadsnakes/python3.7.1 or alternative
Run a command that uses the apt_pkg module and get an error such as;
from CommandNotFound.db.db import SqliteDatabase
File "/usr/lib/python3/dist-packages/CommandNotFound/db/db.py", line 5, in <module>
import apt_pkg
When we install a non-distro python3 version with apt it will set a shared module directory to be that of python3 most usually it will be /usr/lib/python3.
Most of the time this will be ok, but under some circumstances the different versions of python rely on different libraries or shared objects/libraries than the other python version does, so as other answers have pointed out we need to link the .SO to the correct python version. So if we have python3.6 installed on a 64bit system then the apt_pkg .SO link would be
sudo ln -s apt_pkg.cpython-36m-x86_64-linux-gnu.so apt_pkg.so
But the problem lies in the fact that when we install a newer python version the link will update to point to the newest python version, which leads to the error of apt_pkg module not being found.
By checking which version of python ships with your distro you can create the link as shown above.
Or we use a method to offer the command a choice of python versions to link the .SO such as;
sudo ln -s apt_pkg.cpython-{36m,35m,34m}-x86_64-linux-gnu.so apt_pkg.so
Because python will create this link to the newest installed python version we give the command the option to choose from 3 python versions, of which it will choose the highest version given.
This worked for me on after updating python3.7 on ubuntu18.04
cd /usr/lib/python3/dist-packages
sudo cp apt_pkg.cpython-36m-x86_64-linux-gnu.so apt_pkg.so
I see everyone saying how to fix it with strange copying etc, but no one really said why the problem occurs.
So let me explain, for those of you who like me don't want to mess with system files only because someone on SO told them so.
The problem is that:
many system scripts have python3 shebang hardcoded into them. You can check it yourself:
~$ grep -R "\#\!/usr/bin/python3" /usr/lib/*
/usr/lib/cnf-update-db:#!/usr/bin/python3
/usr/lib/command-not-found:#!/usr/bin/python3
/usr/lib/cups/filter/pstotiff:#!/usr/bin/python3
/usr/lib/cups/filter/rastertosag-gdi:#!/usr/bin/python3 -u
grep: /usr/lib/cups/backend/cups-brf: Permission denied
/usr/lib/cups/backend/hpfax:#!/usr/bin/python3
/usr/lib/language-selector/ls-dbus-backend:#!/usr/bin/python3
/usr/lib/python3/dist-packages/language_support_pkgs.py:#!/usr/bin/python3
/usr/lib/python3/dist-packages/softwareproperties/MirrorTest.py:#!/usr/bin/python3
/usr/lib/python3/dist-packages/cupshelpers/installdriver.py:#!/usr/bin/python3
/usr/lib/python3/dist-packages/cupshelpers/openprinting.py:#!/usr/bin/python3
/usr/lib/python3/dist-packages/cupshelpers/xmldriverprefs.py:#!/usr/bin/python3
/usr/lib/python3/dist-packages/cupshelpers/smburi.py:#!/usr/bin/python3
/usr/lib/python3/dist-packages/cupshelpers/ppds.py:#!/usr/bin/python3
/usr/lib/python3/dist-packages/cupshelpers/debug.py:#!/usr/bin/python3
/usr/lib/python3/dist-packages/DistUpgrade/dist-upgrade.py:#!/usr/bin/python3
/usr/lib/python3/dist-packages/CommandNotFound/db/creator.py:#!/usr/bin/python3
/usr/lib/python3/dist-packages/CommandNotFound/db/db.py:#!/usr/bin/python3
/usr/lib/python3/dist-packages/Quirks/quirkreader.py:#!/usr/bin/python3
grep: /usr/lib/ssl/private: Permission denied
/usr/lib/system-service/system-service-d:#!/usr/bin/python3
/usr/lib/ubuntu-release-upgrader/check-new-release-gtk:#!/usr/bin/python3
/usr/lib/ubuntu-release-upgrader/do-partial-upgrade:#!/usr/bin/python3
/usr/lib/ubuntu-release-upgrader/check-new-release:#!/usr/bin/python3
/usr/lib/update-notifier/package-data-downloader:#!/usr/bin/python3
/usr/lib/update-notifier/backend_helper.py:#!/usr/bin/python3
/usr/lib/update-notifier/apt_check.py:#!/usr/bin/python3
/usr/lib/update-notifier/apt-check:#!/usr/bin/python3
python apt package python-apt/python3-apt is a system package, so it's for default system python
Thus, the scripts will always get the version currently linked to python3, but fail because the apt package is not present.
General solution: NEVER change default python3 link. Ever. This also applies to python link - if an app was written in Python2 with some old syntax elements that don't work in Python3, the app will not work.
[My terminal broke that way because I use Terminator, which is apparently written in Python2.7 not compatible with Python3.]
Solutions presented here either suggest copying/linking the apt package files or changing python3 link.
Let's analyse both:
Copying/linking the apt package
This shouldn't be a problem because from around Python3.4 all python scripts work on newer versions as well.
So far. But it may break in the future - if you keep your system long enough.
Changing python3 link back
This is a great solution because we can get back to "never ever changing the link"
"But I like having to type just python!" - I like it too! That's how I got to this problem in the first place!
In general, you should avoid manually changing system links - use update-alternatives instead to link different versions. This applies to any app with many versions. This will still break those system scripts (because it does change the link), but you can switch back and forth easily, without worrying whether you put link and dest in the right order or made a typo.
Consider using other name than python/python3 for your link or alias.
Or add your own python/python3 link to PATH (just like virtual environments do), without changing system links.
The solution of #user8178061 worked well but I did it with some modifications for my version wich is python3.7 with Ubuntu
I replaced the apt_pkg.cpython-3m-i386-linux-gnu.so with apt_pkg.cpython-36m-x86_64-linux-gnu.so
Here the two commands to execute:
cd /usr/lib/python3/dist-packages
sudo cp apt_pkg.cpython-36m-x86_64-linux-gnu.so apt_pkg.so
Check your default Python 3 version:
python3 --version
Python 3.7.5
cd into /usr/lib/python3/dist-packages and check the apt_pkg.* files. You will find that there is none for your default Python version:
ll apt_pkg.*
apt_pkg.cpython-36m-x86_64-linux-gnu.so
Create the symlink:
sudo ln -s apt_pkg.cpython-36m-x86_64-linux-gnu.so apt_pkg.cpython-37m-x86_64-linux-gnu.so
if you're using python 3.7 downgrade it to python 3.6 by updating Alternatives, This worked for me
sudo update-alternatives --install /usr/bin/python3 python3 /usr/bin/python3.6 1
sudo update-alternatives --config python3
For some reason my install was missing apt_pkg.so in the python3 dist-packages dir. (apt_pkg.cpython-33m-x86_64-linux-gnu.so was there?!) but and I had to make a symlink apt_pkg.so -> apt_pkg.cpython-33m-x86_64-linux-gnu.so
in /usr/lib/python3/dist-packages
I'm not sure whether my upgrade was broken or why this was the case. It occured after trying to upgrade (precise->raring->quantal upgrade)
A last resort is sudo cp /usr/lib/python3/dist-packages/apt_pkg.cpython-35m-x86_64-linux-gnu.so /usr/lib/python3/dist-packages/apt_pkg.cpython-36m-x86_64-linux-gnu.so
if the ln command is too much for you or somehow magically doesn't work.
cp above can also be mv if you are only dedicated to using one Python version.
I'm on Ubuntu 16.04, and upgraded to Python 3.7. Here is the error that I had when trying to add a PPA
sudo add-apt-repository ppa:ubuntu-toolchain-r/test
Traceback (most recent call last):
File "/usr/bin/add-apt-repository", line 11, in <module>
from softwareproperties.SoftwareProperties import SoftwareProperties, shortcut_handler
File "/usr/lib/python3/dist-packages/softwareproperties/SoftwareProperties.py", line 27, in <module>
import apt_pkg
ModuleNotFoundError: No module named 'apt_pkg'
I was able to fix this error by making symbolic link with my initial python 3.4 apt_pkg.cpython-34m-x86_64-linux-gnu.so by creating the following symbolic link
sudo ln -s apt_pkg.cpython-34m-x86_64-linux-gnu.so apt_pkg.so
In my case I ran below command and it fixed the error:
sudo apt install --reinstall python3 python python3-minimal --fix-broken
If you're using python 3.5, downgrade to 3.4. That's the safest move to do.
Under /usr/lib/python3/dist-packages you'll see *34m* which python 3.5 can't use. zhazha answer symlink to it.
In addition to making a symbolic link for apt_pkg.so, you may want to make apt_inst.so in the same manner of apt_pkg.so.
ln -s apt_inst.cpython-35m-x86_64-linux-gnu.so apt_inst.so
I tried to create the link but many other problems happened. So, you can select the old version of python to install things using:
sudo update-alternatives --config python3
And return to the desirable version right after using the same command.
Hope it works.
Windows 10 WSL v1 (Ubuntu 16.04.6 LTS)
This reddit answer (slightly modified worked for me)
sudo ln -sfn /usr/lib/python3/dist-packages/apt_pkg.cpython-35m-x86_64-linux-gnu.so apt_pkg.so
After spending 4 hours I have got this solution which finally worked for me I hope this will help...
It is important to understand that sometimes when you upgrade from an older python version some packages stay in the previous version path, so here is what I did:
cd /usr/lib/python3/dist-packages
Check the existence of a file named apt_pkg.cpython-35m-x86_64-linux-gnu.so or 34m or 36m listing the files and when you find it, delete the current apt_pkg.so file in
/usr/lib/python3/dist-packages
Finally create a link with the correct path using apt_pkg.so like this:
cd /usr/lib/python3/dist-packages
sudo ln -s apt_pkg.cpython-35m-x86_64-linux-gnu.so apt_pkg.so
Now you can try again and It should work.
This variant work for me.
cd /usr/lib/python3/dist-packages
ls -la /usr/lib/python3/dist-packages
sudo cp apt_pkg.cpython-38-x86_64-linux-gnu.so apt_pkg.so
If you get an error message saying too many levels of symbolic links as shown below:
cp: failed to access '/usr/lib/python3/dist-packages/apt_pkg.so': Too many levels of symbolic links
Then you need to simply unlink the apt_pkg.so file. Use the following command:
sudo unlink apt_pkg.so
And then use the command
sudo cp apt_pkg.cpython-38-x86_64-linux-gnu.so apt_pkg.so
Good luck!
Original answer: https://askubuntu.com/a/1227625
None of the answers worked for me (I am using Ubuntu 16.04 and Python 3.6). So I finally solved the issue as following:
1- connect to the FTP of the server
2- go to the folder "/usr/lib/python3/dist-packages/"
3- duplicate the file "apt_pkg.cpython-35m-x86_64-linux-gnu.so"
4- rename this duplicated file to "apt_pkg.cpython-36m-x86_64-linux-gnu.so"
That's it!
Well, the cleanest solution for me is to rebuild the related library with your new Python version, in its specific space.
I'm doing this right now, switching from Python3.9 to Python3.10.1.
So:
cd /tmp/
apt source python3-apt
cd python-apt-version-ecc
python3-new-version setup.py build
python3-new-version setup.py install
Done this also with dependencies packages (software-properties, python-launchpadlib, and so on), and now add-apt-repository works like a charm.
Which ones to recompile? Simply watch out the complains of running add-apt-repository.
By the way, I'm on Ubuntu 21.04, but the logic is the same on any Debian like system.
Please review the following documentation.
It could help you to solve the problem.
Solve the problem of replacing the python version with ModuleNotFoundError: No module named 'apt_pkg'
Please try to fix this by setting the locale variables:
export LC_ALL="en_US.UTF-8"
export LC_CTYPE="en_US.UTF-8"
Just in case it helps another, I finally solved this problem, that was apparently caused by python version conflicts, by redirecting the link python3, then redirecting it to the right python version:
sudo rm /usr/bin/python3
sudo ln -s /usr/bin/python3.4
You may need to enter the correct python version, found with:
python3 -V

Categories