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
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 ll 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.

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