With Ubuntu, only certain Python versions are available from the repositories. They're easy to get, but with the rest, it's not so obvious. While I can certainly build them from source, I'm thinking there must be tools to automate the process but I can't find them.
Windows and OS X users can simply use executable installers available on the Python website. This is not true with the other OS options. If your Linux distribution's repositories do not contain all the versions you want, building from source is the recommended way, at least as far as the website is concerned.
Automating this process is possible. pythonbrew is a now-deprecated installation manager that recommends shell script-based pyenv instead. With this, installing a new version is as simple as
pyenv install <version number, e.g. 2.7.3>
Another alternative is the more Python-based (read: cross platform) pythonz, a fork of the original pythonbrew. It is just as easy:
pythonz install <version number, e.g. 2.7.3>
One way of installing multiple versions of Python in Ubuntu is to use Felix Krull's deadsnakes ppa, which includes all the major releases from 2.3 on (not point releases) if they are not already in the Ubuntu repositories. It only supports currently supported Ubuntu versions. There is no guarantee of updates, but it does make getting different versions easy.
To install the necessary repositories:
$ sudo add-apt-repository ppa:fkrull/deadsnakes
$ sudo apt-get update
If you want to install 2.7, it's as easy as:
$ sudo apt-get install python2.7
Note this only works for Ubuntu, not e.g. Debian.
$ sudo add-apt-repository ppa:deadsnakes/ppa
$ sudo apt-get update
To install Python2.7, just enter:
$ sudo apt-get install python2.7
Related
I want to install python 3.8.12 on my ubuntu .
I followed this link: https://tecadmin.net/install-python-3-8-ubuntu/ and installed python in my Download folder and I can't find it at /usr/bin/python3.8.12
Is it right that all the python versions need to be found at /usr/bin ?
Do I need to copy it manually to /usr/bin ?
Is there a way I can install python 3.8.12 with apt-get ?
That article is outdated, most likely written at a time where Python 3.8 was not yet available on the stable Ubuntu repositories.
You can install the latest Python available with just apt install python3 (3.9 at the moment).
If you really want 3.8, I suggest you take a look at the deadsnakes PPA. It contains an archive of all Python packages for Ubuntu, and also newer versions that haven't hit Ubuntu stable yet (like 3.10).
You can add this PPA and install Python 3.8 with just three commands:
add-apt-repository ppa:deadsnakes/ppa
apt update
apt install python3.8
Regarding your other two bullet points:
Yesn't. The thing is that, by default, /usr/bin is included in your PATH environment variable, which what enables you to just type python ... instead of providing the absolute path for the binary. It is also expected by some scripts, I suppose.
You could, and you could also symlink it. The reason why it wasn't put there already is because the article used altinstall, which prevents exactly that. It is way more preferable that you install stuff through your package manager, however.
I'm trying to install an older version of tensorflow and it needs python3.6 to support the whl file of installation.
I'm now running Ubuntu 20.04 with python 3.8.5, I've already done this :
sudo add-apt-repository ppa:deadsnakes/ppa
followed by :
sudo apt-get update
sudo apt-get install python3.6
By doing that it installs python 3.6 but when I see the version of python installed it's still 3.8.5. Should I do something to remove python3.8.5 ? maybe apt-get purge ?
P.S: I'm installing the wheel file through pip3 should I downgrade it too ?
You shouldn't hack the system installation of Python I'd say.
Instead you should use something that let's you manage multiple versions of it, something like pyenv.
It is a well-known and widely accepted utility and according to its readme:
pyenv lets you easily switch between multiple versions of Python. It's simple, unobtrusive, and follows the UNIX tradition of single-purpose tools that do one thing well.
You can find the installation instructions here: https://github.com/pyenv/pyenv#basic-github-checkout.
Once you installed it you can install your preferred Python distribution which will live besides your system one and all the others you want later.
E.g. if you want to install 3.6.7 and then use it globally you can do:
pyenv install 3.6.7
pyenv global 3.6.7
Then test it like:
python -V
And that's only to scratch the surface, you can do many more things with it, check out the documentation for more.
after the commands you've run, you should have a python3.6 binary installed on the path
that said, I'd recommend using virtualenvs instead of system installations
for deadsnakes, you can install the venv module by (sudo) apt install python3.6-venv (debian decided to split venv into a separate module, so the deadsnakes packaging follows that)
from there you can create and activate a virtualenv:
python3.6 -m venv venv # create the environment
. venv/bin/activate # activate the environment
pip install ... # install things to your isolated environment
inside this virtualenv the python command will refer to your own isolated python installation
disclaimer: I'm the maintainer of deadsnakes
I'm trying to install pip and virtualenv on a server (running Ubuntu 12.04.4 LTS) on which I have access, but I can only do it with sudo apt-get install (school politics). The problem is that althought I have run the sudo apt-get update command to update the packages list, I think it keeps installing old ones. After doing sudo apt-get install python-pip python-virtualenv, I do pip --version on which I get the 1.0, and virtualenv --version on which I get 1.7.1.2. These two version are quite old (pip is already in 1.5.5 and virtualenv in 1.11.5). I read that the problem is that the packages list is not up-to-date, but the command sudo apt-get update should solve this, but I guess no. How can I solve this? Thanks a lot!
apt-get update updates packages from Ubuntu package catalog, which has nothing to do with mainstream versions.
LTS in Ubuntu stands for Long Term Support. Which means that after a certain period in time they will only release security-related bugfixes to the packages. In general, major version of packages will not change inside of a major Ubuntu release, to make sure backwards-compatibility is kept.
So if then only thing you can do is apt-get update, you have 2 options:
find a PPA that provides fresher versions of packages that you need, add it and repeat the update/install exercise
find those packages elsewhere, download them in .deb format and install.
If you really need to use the latest stable versions of Python packages, then do not use apt-get for installing Python packages and use pip instead. If you would use apt-get and later install the same packages by means of pip or (better not) easy_install or setup.py, you are likely to run into version conflicts wondering, why your python based commands are of unexpected versions, or even worse, why they do not work at all.
I try to follow this pattern:
1. system wide pip installation first
Using instructions from here: http://pip.readthedocs.org/en/latest/installing.html find get-pip.py script, download it and run as python script.
$ wget https://bootstrap.pypa.io/get-pip.py
$ sudo python get-pip.py
$ rm get-pip.py
2. use pip to install virtualenv system wide
this shall be as easy as:
$ sudo pip install virtualenv
3. (optional) install virtualenvwrapper - system wide or to user profile
$ sudo pip install virtualenvwrapper
and follow instructions for configuring it.
4. Since now, install inside your virtualenv environments
This shall prevent conflicts between various versions of packages.
You are free to update particular virtualenvs as you need one by one independently.
5. (optional) Configure installation cache directories for installation speed
There are method how to speed up repeated installation of packages, what comes handy if you get used using virtualenv often. For details see my answer: https://stackoverflow.com/a/18520729/346478
I have ubuntu 10.04 with python2.6 by default. I have installed python2.7.
When I want to install python packages with
apt-get python-<package>
it gets installed to python2.6. How can I make it to install the package to python2.7? Is there any option?
I have looked at this, but I could not find such directories in my OS. I have considered using easy_install-2.7, but not all packages are supported. For example python-torctl.
I am more interested in binding python2.7 with apt-get install.
Python has got its own package managing facilities, in parallel to the one sets by the Linux distributions (including Ubuntu). The repository is the Pypi - Python Package Index, and packages are installed with pip or the easy_install script, which is part of Python's setuptools package.
As a rule of thumb, you should not use both the packages installed via pip/setuptools, and packages available to your distro (via apt-get, yum, urpmi, etc...) as they might conflict.
So, one of the less error prone way to deal with it is to have separate Python installs in your system - leave the python that came with the system for system scripts and such - on this python, make use of packages installed by your package manager only. And install other versions of Python (or even the same), to be run with "virtualenv"s - on these other install you install things with pip/setuptools only.
(And even if one opt to live boldly and not use virtualenvs, installing another python version on the same prefix (/usr, and even /usr/local) than your system's Python is a source to confusing errors and conflicts).
Note that the Debian - and Ubuntu - systems devised a way to run parallel official Python's in /usr, and to have apt-get to install Python packages to both Python versions at once. This mostly works, but they mess with Python's default directory hierarchy, and some applications fail to use Python in this way. (It is also a mess to find the module files themselves in a Debian or Ubuntu). So the above method apply as a recommendation even if your system do have more than one version of Python available on apt-get.
In short, once you have compiled your desired version of Python, do this:
use your system's package manager to install "python-setuptools" and "python-virtualenv" (not sure if these are the actual package names).
Use virtualenv to create an environment from which you will use your different Python version
Activate your virtualenv, and install Python packages using pip on it.
Virtualenv does feature a "--help" switch to help you, but you basically do:
$ virtualenv -p <path-to-python-interpreter> <environment-dir>
$ source <environment-dir>/bin/activate
And there you are - all things using Python will "see" the interpreter in the virtualenv, due to environment variables set.
ubuntu 10.04 doesn't have a python2.7 package. You have to build 2.7 yourself. I did read an article about ubuntu releasing a python2.7 package when 12.04 came out but i'm not sure what the repository location is.
http://eli.thegreenplace.net/2011/10/10/installing-python-2-7-on-ubuntu/
or:
sudo add-apt-repository ppa:fkrull/deadsnakes
sudo apt-get update
sudo apt-get install python2.7
https://askubuntu.com/questions/101591/install-python-2-7-2-on-ubuntu-10-04-64-bit
this question has lots of answers online.
pyenv
https://github.com/pyenv/pyenv
Pyenv allows you to manage multiple Python versions without sudo for a single user, much like Node.js NVM and Ruby RVM.
Install Pyenv:
curl https://pyenv.run | bash
Then add to your .bashrc:
export PATH="${HOME}/.pyenv/bin:$PATH"
eval "$(pyenv init -)"
eval "$(pyenv virtualenv-init -)"
Find Python version to install:
pyenv install --list
Install the python version you want:
# Increase the chances that the build will have all dependencies.
# https://github.com/pyenv/pyenv/wiki/Common-build-problems
sudo apt build-dep python3
sudo apt-get install -y make build-essential libssl-dev zlib1g-dev libbz2-dev \
libreadline-dev libsqlite3-dev wget curl llvm libncurses5-dev libncursesw5-dev \
xz-utils tk-dev libffi-dev liblzma-dev python-openssl git
# Build and install a Python version from source.
pyenv install 3.8.0
List available Python versions:
pyenv versions
We now have:
* system (set by /home/cirsan01/.pyenv/version)
3.8.0
Select a different python version:
pyenv global 3.8.0
python --version
python3 --version
Both output:
Python 3.8.0
We can now proceed to install and use packages normally:
pip install cowsay
python -c 'import cowsay; cowsay.tux("Python is fun")'
cowsay 'hello'
We can confirm that everything is locally installed in our clean environemnt with:
python -c 'import cowsay; print(cowsay.__file__)'
gives:
/home/ciro/.pyenv/versions/3.8.0/lib/python3.8/site-packages/cowsay/__init__.py
and:
which cowsay
gives:
/home/ciro/.pyenv/shims/cowsay
and:
which python
gives:
/home/ciro/.pyenv/shims/python
Per project usage
In the previous section, we saw how to use pyenv in a global setup.
However, what you usually want is to set a specific python and package version on a per-project basis. This is how to do it.
First install your desired Python version as before.
Then, from inside your project directory, set the desired python version with:
pyenv local 3.8.0
which creates a file .python-version containing the version string.
And now let's install a package locally just for our project: TODO: there is no nice way it seems: Pyenv choose virtualenv directory
Now, when someone wants to use your project, they will do:
pyenv local
which sets the Python version to the correct one.
Related threads:
https://askubuntu.com/questions/682869/how-do-i-install-a-different-python-version-using-apt-get
https://unix.stackexchange.com/questions/9711/what-is-the-proper-way-to-manage-multiple-python-versions
apt-get install for different python versions
Tested on Ubuntu 18.04, pyenv 1.2.15.
Is it this, which people seem to recommend most often:
$ sudo apt-get install python-setuptools
$ sudo easy_install pip
$ sudo pip install virtualenv
Or this, which I got from http://www.pip-installer.org/en/latest/installing.html:
$ curl -O https://github.com/pypa/virtualenv/raw/master/virtualenv.py
$ python virtualenv.py my_new_env
$ . my_new_env/bin/activate
(my_new_env)$ pip install ...
Or something entirely different?
If you can install the latest Python (2.7.9 and up) Pip is now bundled with it.
See: https://docs.python.org/2.7//installing/index.html
If not :
Update (from the release notes):
Beginning with v1.5.1, pip does not require setuptools prior to running get-pip.py. Additionally, if setuptools (or distribute) is not already installed, get-pip.py will install setuptools for you.
I now run the regular:
curl --silent --show-error --retry 5 https://bootstrap.pypa.io/get-pip.py | sudo python
Here are the official installation instructions:
http://pip.readthedocs.org/en/latest/installing.html#install-pip
EDIT 25-Jul-2013:
Changed URL for setuptools install.
EDIT 10-Feb-2014:
Removed setuptools install (thanks #Ciantic)
EDIT 26-Jun-2014:
Updated URL again (thanks #LarsH)
EDIT 1-Mar-2015:
Pip is now bundled with Python
http://www.pip-installer.org/en/latest/installing.html is really the canonical answer to this question.
Specifically, the systemwide instructions are:
$ curl -O http://python-distribute.org/distribute_setup.py
$ python distribute_setup.py
$ curl -O https://raw.github.com/pypa/pip/master/contrib/get-pip.py
$ python get-pip.py
The section quoted in the question is the virtualenv instructions rather than the systemwide ones. The easy_install instructions have been around for longer, but it isn't necessary to do it that way any more.
This answer comes from #webology on Twitter:
$ sudo apt-get install python-setuptools
$ sudo easy_install pip
$ sudo pip install --upgrade pip virtualenv virtualenvwrapper
My added notes:
On Mac/Windows (and Linux if the apt repo is outdated) you'd replace the first step with downloading setuptools from http://pypi.python.org/pypi/setuptools
On Windows you'd have to omit virtualenvwrapper from the last step and install it manually somehow. I don't know if there's a way to do this without Cygwin, but I hope so.
On Ubuntu 12.04 I've had good luck just using the package manager:
sudo apt-get install python-pip virtualenvwrapper
There is no preferred method - everything depends on your needs. Often you need to have different Python interpreters on the system for whatever reason. In this case you need to install the stuff individually for each interpreter. Apart from that: I prefer installing stuff myself instead of depending of pre-packaged stuff sometimes causing issues - but that's only one possible opionion.
There really isn't a single "answer" to this question, but there are definitely some helpful concepts that can help you to come to a decision.
The first question that needs to be answered in your use case is "Do I want to use the system Python?" If you want to use the Python distributed with your operating system, then using the apt-get install method may be just fine. Depending on the operating system distribution method though, you still have to ask some more questions, such as "Do I want to install multiple versions of this package?" If the answer is yes, then it is probably not a good idea to use something like apt. Dpkg pretty much will just untar an archive at the root of the filesystem, so it is up to the package maintainer to make sure the package installs safely under very little assumptions. In the case of most debian packages, I would assume (someone can feel free to correct me here) that they simply untar and provide a top level package.
For example, say the package is "virtualenv", you'd end up with /usr/lib/python2.x/site-packages/virtualenv. If you install it with easy_install you'd get something like /usr/lib/python2.x/site-packages/virtualenv.egg-link that might point to /usr/lib/python2.x/site-packages/virtualenv-1.2-2.x.egg which may be a directory or zipped egg. Pip does something similar although it doesn't use eggs and instead will place the top level package directly in the lib directory.
I might be off on the paths, but the point is that each method takes into account different needs. This is why tools like virtualenv are helpful as they allow you to sandbox your Python libraries such that you can have any combination you need of libraries and versions.
Setuptools also allows installing packages as multiversion which means there is not a singular module_name.egg-link created. To import those packages you need to use pkg_resources and the __import__ function.
Going back to your original question, if you are happy with the system python and plan on using virtualenv and pip to build environments for different applications, then installing virtualenv and / or pip at the system level using apt-get seems totally appropriate. One word of caution though is that if you plan on upgrading your distributions Python, that may have a ripple effect through your virtualenvs if you linked back to your system site packages.
I should also mention that none of these options is inherently better than the others. They simply take different approaches. Using the system version is an excellent way to install Python applications, yet it can be a very difficult way to develop with Python. Easy install and setuptools is very convenient in a world without virtualenv, but if you need to use different versions of the same library, then it also become rather unwieldy. Pip and virtualenv really act more like a virtual machine. Instead of taking care to install things side by side, you just create an whole new environment. The downside here is that 30+ virtualenvs later you might have used up quite bit of diskspace and cluttered up your filesystem.
As you can see, with the many options it is difficult to say which method to use, but with a little investigation into your use cases, you should be able to find a method that works.
Do this:
curl "https://bootstrap.pypa.io/get-pip.py" -o "get-pip.py"
python get-pip.py
pip install virtualenv
See
https://pip.pypa.io/en/latest/installing.html
http://docs.python-guide.org/en/latest/dev/virtualenvs/
Since virtualenvs contain pip by default, I almost never install pip globally. What I do ends up looking more like:
$ sudo apt-get install python-setuptools
$ curl -O http://python-distribute.org/distribute_setup.py
$ sudo python distribute_setup.py
$ sudo easy_install virtualenv
I then proceed to install and set up virtualenvwrapper to my liking and off I go. it might also be worthwhile to take a look at Jeremy Avnet's virtualenv-burrito:
https://github.com/brainsik/virtualenv-burrito
#ericholscher says on Twitter, "The one in the official docs.."
It's a great point, you should do what the docs say.
Quoted from the official pip installation instructions at http://www.pip-installer.org/en/latest/installing.html:
$ curl -O https://github.com/pypa/virtualenv/raw/master/virtualenv.py
$ python virtualenv.py my_new_env
$ . my_new_env/bin/activate
(my_new_env)$ pip install ...
Starting from distro packages, you can either use:
sudo apt-get install python-virtualenv
which lets you create virtualenvs, or
sudo apt-get install python{,3}-pip
which lets you install arbitrary packages to your home directory.
If you're used to virtualenv, the first command gives you everything you need (remember, pip is bundled and will be installed in any virtualenv you create).
If you just want to install packages, the second command gives you what you need. Use pip like this:
pip install --user something
and put something like
PATH=~/.local/bin:$PATH
in your ~/.bashrc.
If your distro is ancient and you don't want to use its packages at all (except for Python itself, probably), you can download virtualenv, either as a tarball or as a standalone script:
wget -O ~/bin/virtualenv https://raw.github.com/pypa/virtualenv/master/virtualenv.py
chmod +x ~/bin/virtualenv
If your distro is more of the bleeding edge kind, Python3.3 has built-in virtualenv-like abilities:
python3 -m venv ./venv
This runs way faster, but setuptools and pip aren't included.
To install pip on a mac (osx), the following one liner worked great for me:
sudo easy_install pip
On Debian the best way to do it would be
sudo apt-get install python-pip
In Raspbian, there is even no need to mention python2.7. Indeed this is best way to install pip if python version in less then 2.7.9.
curl --silent --show-error --retry 5 https://bootstrap.pypa.io/get-pip.py | sudo python
Thanks to #tal-weiss
https://github.com/pypa/pip/raw/master/contrib/get-pip.py is probably the right way now.
I use get-pip and virtualenv-burrito to install all this. Not sure if python-setuptools is required.
# might be optional. I install as part of my standard ubuntu setup script
sudo apt-get -y install python-setuptools
# install pip (using get-pip.py from pip contrib)
curl -O https://raw.github.com/pypa/pip/develop/contrib/get-pip.py && sudo python get-pip.py
# one-line virtualenv and virtualenvwrapper using virtualenv-burrito
curl -s https://raw.github.com/brainsik/virtualenv-burrito/master/virtualenv-burrito.sh | bash
The former method is fine. The only problem I can see is that you might end up with an old version of setuptools (if the apt repository hasn't been kept up-to-date..