Unable to install python3-dev ubuntu

Question

When I tried to install python3-dev using sudo apt-get install python3-dev I got the following message

python3-dev : Depends: libpython3-dev (= 3.4.0-0ubuntu2) but it is not going to be installed
           Depends: python3.4-dev (>= 3.4.0-0~) but it is not going to be installed
E: Unable to correct problems, you have held broken packages.

So I tried installing dependencies libpython3-dev then I got this message

The following packages have unmet dependencies:
 libpython3.4-dev : Depends: libpython3.4-stdlib (= 3.4.0-2ubuntu1.1) but 3.4.3-1ubuntu1~14.04.1 is to be installed
                    Depends: libpython3.4 (= 3.4.0-2ubuntu1.1) but 3.4.3-1ubuntu1~14.04.1 is to be installed
E: Unable to correct problems, you have held broken packages.

However both the dependencies are already installed.I'm using Ubuntu 14.04

When I ran the apt-cache policy python3.4 I got

    python3.4:
    Installed: 3.4.3-1ubuntu1~14.04.1
  Candidate: 3.4.3-1ubuntu1~14.04.1
  Version table:
 *** 3.4.3-1ubuntu1~14.04.1 0
        100 /var/lib/dpkg/status
     3.4.0-2ubuntu1.1 0
        500 http://in.archive.ubuntu.com/ubuntu/ trusty-updates/main amd64 Packages
        500 http://security.ubuntu.com/ubuntu/ trusty-security/main amd64 Packages
     3.4.0-2ubuntu1 0
        500 http://in.archive.ubuntu.com/ubuntu/ trusty/main amd64 Packages

Solution 1

The solution is to wait for the Ubuntu developers to re-upload Python 3.4.3 to the updates repository. This should happen any day now. Keep your eyes on bug #1348954.

Edit: Fixed. Installing python3-dev works again.

Solution 2

Okay So I went through this and temporarily solved the problem by forcefully downgrading my python

apt-get install -y \
  python3.4=3.4.0-2ubuntu1.1 \
  python3.4-minimal=3.4.0-2ubuntu1.1 \
  libpython3.4-stdlib=3.4.0-2ubuntu1.1 \
  libpython3.4-minimal=3.4.0-2ubuntu1.1

Edit: After this reinstall stdlib as it misses some libraries. Removing python3 might remove some packages of your desktop environment reinstall the desktop environment in that case.

I had some issues with lightdm after this. Before removing print the removed packages and reinstall them with new python 3

Comments

[Admin]

Which ubuntu version? Try apt-get clean all then try again.

[Admin]

Still the same error

[Admin]

How did you invoke the command? Make sure your system is up-to-date.

[Admin]

What command? I used sudo apt-get clean all

[Admin]

I mean when u try to install.

[Admin]

I've added in the new edit. I've used apt-get install python3-dev

[Admin]

Ok apt-get upgrade. Make sure system is up to date

[Admin]

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