Updating Python version
 

Currently, I have two versions of Python on my computer. Python 2.x which came with my installation of Ubuntu 16.04 and python 3.5.2 which I downloaded via a: sudo apt-get. Now, I want to upgrade my 3.5.2 too 3.7. I was wondering what is the most efficient way of doing this and can it be done without loosing all the modules I have downloaded for 3.5.2? I already have the tar ball I just am worried about installing everything. I dont want to loose all my modules.

See 2. or (more easily) 3. and substitute 3.6 with 3.7

http://www.python36.com/install-python36-on-ubuntu/

Odd, I was able to run:

sudo add-apt-repository ppa:jonathonf/python-3.7

but when I ran:

sudo apt install python3.7

I got an error:

Reading package lists... Done
Building dependency tree
Reading state information... Done
E: Unable to locate package python3.7
E: Couldn't find any package by glob 'python3.7'
E: Couldn't find any package by regex 'python3.7'

Did you run sudo apt update to refresh the package indices after adding the repository?

Yes Sr I did do that.

Ok. Let's have a look at your software sources to see if the repository was correctly added.

Please paste the output from:

If inxi isn't installed on your system, install it with sudo apt install inxi.

Repos: Active apt sources in file: /etc/apt/sources.list
deb http://us.archive.ubuntu.com/ubuntu/ xenial main restricted
deb http://us.archive.ubuntu.com/ubuntu/ xenial-updates main restricted
deb http://us.archive.ubuntu.com/ubuntu/ xenial universe
deb http://us.archive.ubuntu.com/ubuntu/ xenial-updates universe
deb http://us.archive.ubuntu.com/ubuntu/ xenial multiverse
deb http://us.archive.ubuntu.com/ubuntu/ xenial-updates multiverse
deb http://us.archive.ubuntu.com/ubuntu/ xenial-backports main restricted universe multiverse
deb http://security.ubuntu.com/ubuntu xenial-security main restricted
deb http://security.ubuntu.com/ubuntu xenial-security universe
deb http://security.ubuntu.com/ubuntu xenial-security multiverse
Active apt sources in file: /etc/apt/sources.list.d/dominik-stadler-ubuntu-dsta-xenial-ppa-xenial.list
deb http://ppa.launchpad.net/dominik-sta...ial-ppa/ubuntu xenial main
Active apt sources in file: /etc/apt/sources.list.d/getdeb.list
deb http://archive.getdeb.net/ubuntu trusty-getdeb apps
Active apt sources in file: /etc/apt/sources.list.d/jonathonf-ubuntu-python-3_7-xenial.list
deb http://ppa.launchpad.net/jonathonf/python-3.7/ubuntu xenial main
Active apt sources in file: /etc/apt/sources.list.d/openjdk-r-ubuntu-ppa-xenial.list
deb http://ppa.launchpad.net/openjdk-r/ppa/ubuntu xenial main
Active apt sources in file: /etc/apt/sources.list.d/webupd8team-ubuntu-java-xenial.list
deb http://ppa.launchpad.net/webupd8team/java/ubuntu xenial main

Thanks. Ok, it's there. Can you please paste the full output from sudo apt update.

Note that you should enclose all output here within CODE tags (see the # on LQ's advanced edit menu).

Yep np:

Thanks. I wonder what the metadata that was ignored was?

Let's see if Python 3.7's in the cache.

Edit: I have the tarball. Can I just unpack it in usr/local/lib?

I suspect that there's a problem with the PPA. You should contact the maintainer and ask them what's up. It might just be a temporary problem.

Sorry, PPA? Is that the repository hosted by this jonathonf fellow?

Yes. A PPA is a Personal Package Archive. That's what you added to your software sources.

Just a thought. Disable the PPA and then run apt update again - if you don't receive the same "AppStream cache update completed, but some metadata was ignored due to errors" message then faulty metadata at that PPA is most probably to blame.