I've installed virtualenv via pip and get this error after creating a new environment:
selenium:~ auser$ virtualenv new
New python executable in new/bin/python
ERROR: The executable new/bin/python is not functioning
ERROR: It thinks sys.prefix is u'/System/Library/Frameworks/Python.framework/ Versions/2.6' (should be '/Users/user/new')
ERROR: virtualenv is not compatible with this system or executable
In my environment:
PYTHONPATH=/System/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/site-packages
PATH=/System/Library/Frameworks/Python.framework/Versions/2.6/bin:/Library/Frameworks/Python.framework/Versions/2.6/bin:/Library/Frameworks/Python.framework/Versions/2.6/bin:/usr/bin:/bin:/usr/sbin:/sbin:/usr/local/bin:/usr/X11/bin
How can I repair this?
Thanks.
Just in case there's someone still seeking for the answer.
I ran into this same problem just today and realized since I already have Anaconda installed, I should not have used pip install virtualenv to install virtual environment as this would give me the error message when trying to initiate it later. Instead, I tried conda install virtualenv then entered virtualenv env_mysite and problem solved.
Like #RyanWilcox mentioned, you might be inadvertently pointing virtualenv to the wrong Python installation. Virtualenv comes with a -p flag to let you specify which interpreter to use.
In my case,
virtualenv test_env
threw the same error as yours, while
virtualenv -p python test_env
worked perfectly.
If you call virtualenv -h, the documentation for the -p flag will tell you which python it thinks it should be using; if it looks wonky, try passing -p python. For reference, I'm on virtualenv 1.11.6.
In case anyone in the future runs into this problem - this is caused by your default Python distribution being conda. Conda has it's own virtual env set up process but if you have the conda distribution of python and still wish to use virtualenv here's how:
Find the other python distribution on your machine: ls -ls /usr/bin/python*
Take note of the availble python version that is not conda and run the code below (note for python 3 and above you have to upgrade virtualenv first): virtualenv -p python2.7(or your python version) flaskapp
I've run across this problem myself. I wrote down the instructions in a README, which I have pasted below....
I have found there are two things that work:
Make sure you're running the latest virtualenv (1.5.1, of this writting)
If you're using a non system Python as your standard Python (which python to check) Forcefully use the System supplied one.
Instead of virtualenv thing use /usr/bin/python2.6 PATH/TO/VIRTUALENV thing (or whatever which
python returned to you - this is what it did for me when I ran into this issue)
I had the same problem and as I see it now, it was caused by a messy Python installation. I have OS X installed for over a year since I bought a new laptop and I have already installed and reinstalled Python for several times using different sources (official binaries, homebrew, official binaries + hand-made adjustments as described here). Don't ask me why I did that, I'm just a miserable newbie believing everything will fix itself after being re-installed.
So, I had a number of different Pythons installed here and there as well as many hardlinks pointing at them inconsistently. Eventually I got sick of all of them and reinstalled OS X carefully cleaned the system from all the Pythons I found using find utility. Also, I have unlinked all the links pointing to whatever Python from everywhere. Then I've installed a fresh Python using homebrew, installed virtualenv and everything works as a charm now.
So, my recipe is:
sudo find / -iname "python*" > python.log
Then analyze this file, remove and unlink everything related to the version of Python you need, reinstall it (I did it with homebrew, maybe official installation will also work) and enjoy. Make sure you unlink everything python-related from /usr/bin and /usr/local/bin as well as remove all the instances of Frameworks/Python.framework/Versions/<Your.Version> in /Library and /System/Library.
It may be a dirty hack, but it worked for me. I prefer not to keep any system-wide Python libraries except pip and virtualenv and create virtual environments for all of my projects, so I do not care about removing the important libraries. If you don't want to remove everything, still try to understand whether your Pythons are, what links point to them and from where. Then think what may cause the problem and fix it.
I ran into a variation of this "not functioning" error.
I was trying to create an environment in a folder that included the path ".../Programming/Developing..." which is actually "/Users/eric/Documents/Programming:Developing/"
and got this error:
ImportError: No module named site
ERROR: The executable env/bin/python2.7 is not functioning
ERROR: It thinks sys.prefix is u'/Users/eric/Documents/Programming:Developing/heroku' (should be u'/Users/eric/Documents/Programming:Developing/heroku/env')
ERROR: virtualenv is not compatible with this system or executable
I tried the same in a different folder and it worked fine, no errors and env/bin has what I expect (activate, etc.).
I got the same problem and I found that it happens when you do not specify the python executable name properly. So for python 2x, for example:
virtualenv --system-site-packages -p python mysite
But for python 3.6 you need to specify the executable name like python3.6
virtualenv --system-site-packages -p python3.6 mysite
On on OSX 10.6.8 leopard, after having "upgraded" to Lion, then downgrading again (ouch - AVOID!), I went through the Wolf Paulus method a few months ago, completely ignorant of python. Deleted python 2.7 altogether and "replaced" it with 3.something. My FTP program stopped working (Fetch) and who knows what else relies on Python 2.7. So at that point I downloaded the latest version of 2.7 from python.org and it's installer got me up and running - until i tried to use virtualenv.
What seems to have worked for me this time was totally deleting Python 2.7 with this code:
sudo rm -R /System/Library/Frameworks/Python.framework/Versions/2.7
removing all the links with this code:
sudo rm /usr/bin/pydoc
sudo rm /usr/bin/python
sudo rm /usr/bin/pythonw
sudo rm /usr/bin/python-config
I had tried to install python with homebrew, but apparently it will not work unless all of XTools is installed, which I have been avoiding, since the version of XTools compatible with 10.6 is ancient and 4GB and mostly all I need is GCC, the compiler, which you can get here.
So I just installed with the latest download from python.org.
Then had to reinstall easy_install, pip, virtualenv.
Definitely wondering when it will be time for a new laptop, but there's a lot to be said for buying fewer pieces of hardware (slave labor, unethical mining, etc).
The above solutions failed for me, but the following worked:
python3 -m venv --without-pip <ENVIRONMENT_NAME>
. <ENVIRONMENT_NAME>/bin/activate
curl https://bootstrap.pypa.io/get-pip.py | python
deactivate
It's hacky, but yes, the core problem really did just seem to be pip.
I did the following steps to get virtualenv working :
Update virtualenv as follows :
==> sudo pip install --upgrade virtualenv
Initialize python3 virtualenv :
==> virtualenv -p python3 venv
I had this same issue, and I can confirm that the problem was with an outdated virtualenv.py file.
It was not necessary to do a whole install --upgrade.
Replacing the virtualenv.py file with the most recent version sufficed.
I also had this problem, and I tried the following method which worked for me:
conda install virtualenv
virtualenv --system-site-packages /anaconda/envs/tensorflow (here envs keeps all the virtual environments made by user)
source /anaconda/envs/tensorflow/bin/activate
Hope it's helpful.
I had this same issue when trying to install py2.7 on a newer system. The root issue was that virtualenv was part of py3.7 and thus was not compatible:
$ virtualenv -p python2.7 env
Running virtualenv with interpreter /usr/local/bin/python2.7
New python executable in /Users/blah/env/bin/python
ERROR: The executable /Users/blah/env/bin/python is not functioning
ERROR: It thinks sys.prefix is u'/Library/Frameworks/Python.framework/Versions/2.7' (should be u'/Users/blah/env')
ERROR: virtualenv is not compatible with this system or executable
$ which virtualenv
/Library/Frameworks/Python.framework/Versions/3.7/bin/virtualenv
# install proper version of virtualenv
$ pip2.7 install virtualenv
$ /Library/Frameworks/Python.framework/Versions/2.7/bin/virtualenv -p python2.7 env
$ . ./env/bin/activate
(env) $
Open terminal and type /Library/Frameworks/Python.framework/Versions/
then type ls /Library/Frameworks/Python.framework/Versions/2.7/bin/
if you are using Python2(or any other else).
Edit ~/.bash_profile and add the following line:
export PATH=$PATH:/Library/Frameworks/Python.framework/Versions/2.7/bin/
cat ~/.bash_profile
In my case the content of ~/.bash_profile is as follows:
export PATH=$PATH:/Library/Frameworks/Python.framework/Versions/2.7/bin/
Now the virtualenv command should work.
If you continue to have trouble with virtualenv, you might try pythonbrew, instead. It's an alternate solution to the same problem. It works more like Ruby's rvm: It builds and creates an entire instance of Python, under $HOME/.pythonbrew, and then sets up some bash functions that allow you to switch easily between versions. Where virtualenv shadows the system version of Python, using symbolic links as part of its solution, pythonbrew builds entirely self-contained installations of Python.
I used virtualenv for years. It's a decent solution, but I've switched to pythonbrew lately. Having completely self-contained Python instances means that installing a new one takes awhile (since pythonbrew actually compiles Python from scratch), but the self-contained nature of each installation appeals to me. And disk is cheap.
Related
I've just installed Python version 3.11 (I also moved versions 3.8 and 3.9 to the trash from my Applications folder).
I can see it in the following:
$ myname#name-MBP miniconda3 % ls /usr/local/bin/py*
/usr/local/bin/pydoc3 /usr/local/bin/python3-intel64
/usr/local/bin/pydoc3.11 /usr/local/bin/python3.11
/usr/local/bin/python3 /usr/local/bin/python3.11-config
/usr/local/bin/python3-config /usr/local/bin/python3.11-intel64
(Any additional recommendations on whether I need to clean things up would be much appreciated.)
Checking python3 --version still displays Python 3.8.13.
First attempt to solve
Initially I tried installing it from the command line using homebrew and specifying the version:
brew install python#3.11
I also tried using conda, but neither of these worked.
Second attempt to solve
My initial thought was to check my PATH (I think this is how Python decides which version to use, but please correct me if I'm wrong).
This still only contained version 8 paths:
/Users/myname/miniconda3/lib/python38.zip
/Users/myname/miniconda3/lib/python3.8
/Users/myname/miniconda3/lib/python3.8/lib-dynload
/Users/myname/.local/lib/python3.8/site-packages
/Users/myname/miniconda3/lib/python3.8/site-packages
So I added the Python3.11 path to it using
PYTHONPATH="/usr/local/bin/pydoc3.11/:$PYTHONPATH"
export PYTHONPATH
Now it includes the v3.11 path when I print out sys.path:
/usr/local/bin/python3.11
/usr/local/bin/pydoc3.11
/Users/myname/miniconda3
/Users/myname/miniconda3/lib/python38.zip
/Users/myname/miniconda3/lib/python3.8
/Users/myname/miniconda3/lib/python3.8/lib-dynload
/Users/myname/.local/lib/python3.8/site-packages
/Users/myname/miniconda3/lib/python3.8/site-packages
But the python3 --version output is still unchanged.
Questions
I'm nervous to keep playing around with the contents of my path and entering random command line executions to try to solve this because I really have no clue what I'm doing.
What's happening here?
How can I get the output of python3 --version to be 3.11?
So first thing to understand is setting the variable PYTHONPATH will not affect which version of python is executed by the shell. The shell (bash/zsh) only knows to scan the paths in the PATH env var to figure out all the executables.
Now there are two ways to solve this.
1. Using the python#3.11 from homebrew.
There are several downsides to using this method. Currently, the default python3 by brew is 3.10.x. Whenever you will install any cask or formula that depends on python#3, it'll invariably install the python#3 formula aka 3.10.x. Installing python3 will make brew symlink 3.10.x into /opt/homebrew/bin.
Python 3.11.x can be used by installing python#3.11 and invoking python3.11. This should drop you into the Python 3.11 interpreter. Append all python executable names with the version like pip will be pip3.11
Trying to force 3.11 over 3.10 links will be complicated and cause instability. It'll only cause frustration during development.
2. Using VirtualEnvs
Your best bet for the most stable and no-headache approach to python is to create virtual envs using either venv or pyenv. use pyenv-virtualenv for max ease of use.
One limitation of venv is that it'll create a virtualenv of the same version that invoked it. Aka if you do brew install python#3 && python3 -m venv <folder>, it'll create virtualenv of python3. For 3.11 you'll have to brew install python#3.11 && python3.11 -m venv <folder>. Pyenv on the other hand can install any version of python.
Go through https://www.dataquest.io/blog/a-complete-guide-to-python-virtual-environments/ and https://github.com/pyenv/pyenv-virtualenv to understand and learn more.
I had python2 installed in my ubuntu (19.04) and I wanted to get it upgraded to 3.7. I installed the 3.7 but still the version showed as 2.7. but I could run python3 and go to the console and python3.7 executable was available in /usr/bin. Did try all the tricks available in internet without any luck. then I decided to delete python2.7 executable from the /usr/bin and now I cannot even run pip as it tries to find the deleted 2.7 I guess. Getting the following message.
bash: /usr/bin/pip: /usr/bin/python: bad interpreter: No such file or directory
I don't know why it's still trying to find 2.7 like ex girl friend when 3.7 is installed and available in the machine.
Did you set up a path for python 3.7 in your .bashrc file? If not, try that and that should help.
Usually a path is something like:
$ export PATH=$HOME/Nek5000/bin:$PATH
First, run an update to make sure that there aren’t newer versions of the required packages.
sudo apt update --fix-missing
Next, you can try forcing Apt to look for and correct any missing dependencies or broken packages. This will actually install any missing packages and repair existing installs.
sudo apt install -f
(Source)
Also, always remember - never install directly in global environment. You should always create a local environment first(i recommend venv) as there are very high chances you can break something globally.
You can create a local environment by -
python3 -m venv tutorial-env
where tutorial-env is the name of your environment.
To activate this environment, you should run
source tutorial-tutorial-env/bin/activate
I had python 3.4 in my virtualenv, but after upgrading ubuntu to 16.04 python upgraded to 3.5 so python in virtualenv crashes with these errors:
Could not find platform independent libraries <prefix>
Could not find platform dependent libraries <exec_prefix>
Consider setting $PYTHONHOME to <prefix>[:<exec_prefix>]
Fatal Python error: Py_Initialize: Unable to get the locale encoding
ImportError: No module named 'encodings'
Current thread 0x00007f2f2dbcb700 (most recent call first):
fish: “python” terminated by signal SIGABRT (Abort)
How can i fix it?
I fixed this by installing the minimum working python3.4 so that my virtualenv worked well enough to get the list of packages, then made a new one with python3.5... as follows:
Get python3.4 minimal packages:
wget http://launchpadlibrarian.net/221250032/python3.4-minimal_3.4.3-1ubuntu1~14.04.3_amd64.deb
wget http://launchpadlibrarian.net/221250033/libpython3.4-minimal_3.4.3-1ubuntu1~14.04.3_amd64.deb
sudo dpkg -i --force-breaks libpython3.4-minimal_3.4.3-1ubuntu1~14.04.3_amd64.deb
sudo dpkg -i python3.4-minimal_3.4.3-1ubuntu1~14.04.3_amd64.deb
My virtualenv is here: ~/virtualenv/example
Get the list of packages in your virtualenv (which should now work well enough for this, but might not do other things properly):
source ~/virtualenv/example/bin/activate
pip freeze > /tmp/requirements.txt
deactivate
Get rid of python3.4, to return to Ubuntu 16.04's preferred state:
sudo dpkg --purge python3.4-minimal
sudo dpkg --force-depends --purge libpython3.4-minimal
Make a new virtualenv with the right packages:
virtualenv -p python3.5 example
source ~/virtualenv/example/bin/activate
pip install -r /tmp/requirements.txt
That should now work, with all your old packages but in python3.5. Should...
See also Upgrade python in a virtualenv
I have same issue and i solved recreating the whole virtualenv
PS: Sorry for my bad English.
I had the same problem today and that is how I have solved it:
Problem:
Firstly, as I understand, the problem occurs because after upgrading to Ubuntu 16.04 the previous version of Python also upgrades. As a result symbolic links inside any Python3 environment are not working anymore.
Solution 1: As it was written above the straightforward solution is to remove all the Python3 environments and create them again. I don't like it because it is second time I do it after upgrading Ubuntu. Also probably I need to use multiple Python 3 versions in the future projects.
Solution 2: That is what I have tried today and it is working fine. Instead of using virtualenv + virtualenvwrapper I decided to try combination of pyenv + pyenv-virtualenv.
The main difference between two approaches is:
Pyenv actually copies an entire Python
installation every time you create a new pyenv version. In contrast,
virtualenv makes use of symbolic links to decrease the size of the
virtualenv’s.
Howto:
Install pyenv as described here together with required versions of Python 2 and 3.
Have a look here on how you can work with virtualenv using pyenv.
Create new environment, install all the dependencies with pip and hopefully forget about the problem of broken symlinks during next Ubuntu upgrade.
I experienced the same issue and I managed to "fix" is by recreating the virtualenv and reinstalling the required packages using pip.
Create a new virtualenv:
virtualenv <new-virtualenv>
Activate it:
source <new-virtualenv>/bin/activate
Install the packages:
pip install <required-packages>
And I was good to go again!
You can keep the old virtualenv by just renaming the folder:
mv <old-virtualenv> <old-virtualenv>-backup
I fixed it by creating a new virtualenv and copying the python executable into the old broken virtualenv.
I am trying to find out why my virtualenv and/or virtualenv wrapper - installed using pip using homebrew - cannot be found. I think it's because it's not added to my PATH:
$ which virtualenv
$
and:
$ virtualenv someDir
$ -bash: virtualenv: command not found
I installed pip using homebrew, and virtualenv using pip, without problems. I tried reinstalling virtualenv, but that did not work either.
How do I know what path to add to PATH? Just the path that virtualenv.py seems to be installed into? That seems to be:
/usr/local/lib/python2.7/site-packages/virtualenv.py
I also found this guide, which suggests this:
$ ln -s ../Cellar/python/2.7/Frameworks/Python.framework/Versions/2.7/bin/virtualenv virtualenv
However, it does not help me run virtualenv. I am on Mac OSX 10.7.5 (Lion).
It seems that I myself am the exception to the rule for almost all 'simple' installation procedures. For some reason, it WAS a path related issue:
I ran brew info python, which outputted a lot of information. At the bottom I found this:
Executable python scripts will be put in:
/usr/local/share/python
so you may want to put "/usr/local/share/python" in your PATH, too.
I added that to my PATH in /etc/launchd.conf and ~/.bashrc and lo and behold:
$ which virtualenv
tells me:
"/usr/local/share/python/virtualenv"
I still don't know why I couldn't find any pointers in the right direction, online, anywhere? Is pip install virtualenv supposed to add to the PATH itself? If so, why not on my system? Why did #bibhas tell me explicitly it was not a path issue?
Had the same issue after pip install virtualenv
When I inspected python ls -la /usr/local/bin/python I found it was symbolically linked to /Library/Frameworks/Python.framework/Versions/2.7/bin/python
When I cd in that directory I also found the virtualenv executable and
Fixed it by
cd /Library/Frameworks/Python.framework/Versions/2.7/bin
ln virtualenv /usr/local/bin/virtualenv
Sidenote: I also happen to have a python installation in /System/Library/Frameworks/Python.framework/Versions/2.7/bin
I believe that's the one that came with OSX
In your .bashrc you need to have:
export WORKON_HOME=~/.virtualenvs
source /usr/local/bin/virtualenvwrapper.sh
(Mac / Linux specific)
So I got an error message when I did a pip3 install --user --upgrade virtualenv telling me that I did not have Users/home/Library/Python/3.7/bin in my PATH. So I simply added it.
If this is on the Mac, the following did it for me
vi ~/.bash_profile
PATH="/Users/home/Library/Python/3.7/bin:/Library/Frameworks/Python.framework/Versions/3.7/bin:${PATH}"
restart your terminal and type virtualenv env and that should do it.
I solved it by:
At first, I found out it is located at /usr/local/python3
and then I fixed it by the command:
ln virtualenv /usr/local/bin/virtualenv
This solution will give you an alternate tool to use and solve your virtualenv problem at the same time.
Use pythonbrew. It is inspired from rvm in the ruby world and is helpful in managing pythons on your system and also wrap virtualenv commands to provide virtual environment management. I use it Mountain Lion for my development purposes and have had no problems. More details (on my blog): http://stacktoheap.com/blog/2013/03/11/why-use-virtualenv-when-there-is-pythonbrew/
My idea is to add your virtualenv position to the BASH PATH
export PATH=$PATH:/usr/local/python2.7/bin
Or change your position
For those with Python 2.7, I came across this as well, and solved it by simply putting the following line into the \etc\paths file (may need to $ sudo chmod it first):
/Library/Frameworks/Python.framework/Versions/2.7/bin
Save the change and start a new Terminal session. Check it with echo $PATH
The module in /usr/local/lib/python2.7/site-packages is imported by a short script that uses pkg_resources.load_entry_point to run the application. The utility script should be in /usr/local/bin.
So I have read this - https://wiki.archlinux.org/index.php/Python
And it is clear from this wiki that I can install Python 2.7.2 via
pacman -S python2
Is it reasonable for me to create a symlink to python2
ln -s python2 /usr/bin/python
if I don't forsee myself switching to python 3.0 any time soon? Or is there a better way of managing multiple python versions like what I usually use on a debian system (update-alternatives --config python) or on a mac os x system (python select)?
CLARIFICATION:
What I am trying to find out is - what is the "best practice" of managing various python versions on an archlinux system?
I am new to archlinux but familiar with ubuntu, debian and mac os x
I would argue you shouldn't create any symlinks like this at all. Especially if you are going to distribute some of your python code, you should not assume a user has python2 or python3 at /usr/bin/python.
If your script requires python2, just use:
#!/usr/bin/env python2
If your script requires python3, use:
#!/usr/bin/env python3
This way your scripts will work fine even through updates to Python. It will also be much more clear what version your script actually needs.
Most unices already have a /usr/bin/python. Overwriting that one is a bad idea, as this is the Python version used by all packages in the system, and changing that one may break them. When installing the Python 2.7 package the executable should be installed as /usr/bin/python2.7 (if not I would claim Archlinux is broken) and it's better to use that when you want to run Python 2.7.
Archlinux is a bit special, since it will use /usr/bin/python for Python 3, despite the default executable name for Python 3 being /usr/bin/python3. This is confusing and can be seen as a bug, but it does mean you can't use that symlink for Python 2, as any other Archlinux script that uses Python 3 will almost certainly break if you do.
So where on other Unices, symlinking /usr/bin/python to Python 2.7 is a bad idea, on Archlinux it is a terrible idea. Instead just install all version you need and call them with /usr/bin/pythonX.X.
There is a nice project on github what helps you with it's called pyenv
What helps you to manage multiple python instances
As others have said, the short answer is "don't do this, it will most likely break things on your system", however, if you mostly use Python 2 you can still set your personal default in your shell (and still have the option of switching to Python 3 at any time). To do this, first become root and install python2-virtualenv:
# pacman -S python2-virtualenv
Then create a virtual environment that uses Python 2 (this will automatically install Python, setuptools, wheel, and pip in the environment):
$ virtualenv -p /usr/bin/python2 --system-site-packages ~/env # (Or wherever you want your environment to live)
If you only want to use locally installed packages (eg. packages you install with pip and not the ones installed by pacman) remove the --system-site-packages option when creating your environment.
Now in your ~/.bash_profile or ~/.profile (or whatever your preferred shells configuration file is), set something like the following:\
source ~/env/bin/activate
This will activate the virtual environment, making your default version Python 2.
This could still break anything that is launched in a shell, but it's not likely that anything will be unless you're explicitly running it from a shell, at which point you can turn the virtual environment off by running:
deactivate
or simply manually run Python 3.
I just stumbled over this post, no necro-bumping intended but I was wondering nobody mentioned virtualenvs. I'm using ArchLinux as well and I use the python packages virtualenv and virtualenvwrapper to create multiple python environments. You can reference to the python 2 or python3 binaries in /usr/bin/ to determine the python version used in the virtual environment.
The benefit is that packages installed in a virtual environment don't mess with the python the system is using and there are many ways to automate project handling.
I know this may be a very old answer, but it took me two days to solve the problem so I'm going to share.
The proper way to manage python versions in your system to work on different projects without them driving you crazy is to use pyenv and its plugins pyenv-virtualenv and pyenv-virtualenvwrapper as described by Henrique Bastos into this blog post. Notice that this way to work is kinda platform independent, since pyenv is a python package and it can be run quite similarly on Windows, Linux and Mac OSx.
The problems start with Arch Linux. The OS doesn't provide a pacman version of pyenv, so you have to install it cloning it from github as described in the installation section of the release. The installation process is the same both for pyenv-virtualenv and pyenv-virtualenvwrapper. Notice that the shell initialization configuration may be different, in my case it didn't work for ~/.bash_profile, but worked for ~/.bashrc .
Running pyenv is not straightforward if your installation is very fresh like the one I'm setting up in these days, since pip requires openSSL and even if you install it via pacman, pyenv doesn't see it. So, if you want to install an older version of Python (namely 3.4.3), you will find the shell complaining about you haven't installed the openSSL plugin, even if you have it. To be honest, I didn't have the right packages the first time I tried to install it; you have to download the following packages
sudo pacman -S openssl
sudo pacman -S openssl-1.0
sudo pacman -S python-pyopenssl
sudo pacman -S python2-pyopenssl
The way I solved the problem is to add the flags as described in the pyenv installation FAQs: that solution eventually led me to install the python version I wanted:
LDFLAGS="-L/usr/lib/openssl-1.0" \
CFLAGS="-I/usr/include/openssl-1.0" \
pyenv install -v 3.4.3
To avoid to go on the FAQs page everytime you want to renew the python installation environment, you can add an alias in ~/.bashrc or whatever is you shell as follows:
echo alias pyenv='LDFLAGS="-L/usr/lib/openssl-1.0" \
CFLAGS="-I/usr/include/openssl-1.0" \
pyenv' >> ~/.bashrc
In this way you can install python properly with a clean pyenv syntax, and manage it via its plugins in the same way (since the syntax is pyenv [COMMAND] [OTHERSTUFF]).
No, there is no better way to do this. The python symlink is part of the Python 3 package.
I guess changing this link won't break anything for now but it might be possible that some packages will depend on it in the future.