I'm attempting to use pipenv and pyenv to create a virtual environment using python 3.9.0 for a project, but am not able to get pipenv to recognize the version of python 3.9.0 installed by pyenv. Oddly, using pyenv python 3.8.6 works just as expected, and I'm specifying the specific python I want pipenv to use, similar to this answer.
I'm running Catalina 10.15.7 and had a coworker reproduce this exact same behavior on his machine.
Both Pipenv and pyenv have been installed via Homebrew. I have since tried uninstalling homebrew Pipenv and reinstalling with pip, with the same results.
To Reproduce
I successfully ran pyenv install 3.9.0, and when I run pyenv versions, I see:
system
3.8.6
3.9.0
Just as I'd expect.
Inside my working directory, I run pyenv local 3.9.0 to switch my local version of python, followed by pyenv version, which returns returns:
3.9.0 (set by /Users/my-name/myproject)
indicating that the local version was set.
To double check, running pyenv which python returns:
/Users/my-name/.pyenv/versions/3.9.0/bin/python
Now, if I run pipenv install --python 3.9.0 I get the following:
This already is suspect, since 3.9.0 is my local version already. If I respond with y, I get:
Which seems odd, as when I run python, I get to python 3.9.0, so clearly it is on my path. A Pipfile is not created for me, and I don't get a pipenv virtual environment.
Now, if instead I run pipenv install --python $PIPENV_PYTHON, which should in theory use the version of python on my path (which, again, should be 3.9.0), I get this:
Notice how it says "using /users/..../python (3.9.0) to create virtualenv", which is correct, however the next line down says "created virtual environment CPYTHON3.8.6...".
Now, if I repeat the above steps using python 3.8.6, everything works fine.
Additionally, if I specify pipenv --python ~/.pyenv/versions/3.9.0/bin/python3.9, that also seems to work fine -- so for some reason it's not respecting the version, but it is respecting the binary.
The same is true if I run pipenv install --python $(pyenv which python), since it's effectively the same thing as the above command.
For reference my environment vars:
PIP_PYTHON_PATH=/usr/local/Cellar/pipenv/2020.11.15/libexec/bin/python <- perhaps this is a problem?
PIPENV_ACTIVE=1
PIPENV_PYTHON=/Users/myname/.pyenv/shims/python
PYENV_ROOT=/Users/myname/.pyenv
And my $PATH starts with PATH=/Users/my-name/.pyenv/shims:
I do happen to have python 3.8 and python 3.9 installed via homebrew as well, however I'm not trying to use these, and since my path leads off with the shims, I feel like this should not be a problem. Running which python3 and which python both point to the "shims" folder.
Summary
Pipenv is not respecting my pyenv shims, despite the fact that my PYENV_ROOT and my PATH are set correctly. Running pipenv install --python $(pyenv which python) works, specifying a python version does not.
Is this a problem with pipenv, or pyenv, or something that I'm doing?
Per the pipenv docs:
Pipenv by default uses the Python it is installed against to create
the virtualenv. You can set the --python option to $(pyenv which python) to use your current pyenv interpreter.
It was probably using your system python versions rather than your shims
Related
I am currently running python 3.9.13 on my mac. I wanted to update my version to 3.10.10
I tried running
brew install python
However it says that "python 3.10.10 is already installed"!
When i run
python3 --version
in the terminal it says that i am still on "python 3.9.13"
So my question is, how do i change the python version from 3.9.13 to 3.10.10? I already deleted python 3.9 from my applications and python 3.10 is the only one that is still there.
I also tried to install python 3.10.10 from the website and installing it. However it does not work. Python 3.10.10 is being installed successfully but the version is still the same when i check it.
Python 3.10.10 is already installed along with Python 3.9.13. Your path is probably pointing to 3.9.13 and that's why you're getting that Python version.
Try modifying your path variable to point to brew's Python installation, or (better yet) make use of a virtual environment.
a) Telling what Python version your PATH variable is pointing to:
$ which python
Will tell you what's the actual executable's path. That way, you are going to see exactly where you main python resides.
b) If you want to create a virtual environment with brew's python try something like:
$ /usr/local/Cellar/python#3.10/3.10.1/bin/python3 -m venv py310
$ source venv/bin/activate
$ python
> # you should be inside a 3.10.1 envornamente
> CTRL+D
$ pip install requests
you can use pyenv to work with multiple python environments
things to do:
install pyenv : brew install pyenv
install particular python: pyenv install 3.10.10
set python3.10.10 to gloabal python env: pyenv global 3.10.10
and can start using python 3.10.10 version
Just delete the current python installation on your device and download the version you want from the offical website. That is the easiest way and the most suitable one for a beginner.
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.
My Ubuntu system is on python 2.7.15
conda install -c anaconda flask
Anaconda always installs python 3.5 with Flask and other packages. How can I not install python 3.7 and leave python 2.7.15 as is when installing anaconda packages?
The Python you install with anaconda does not interfere at all with your system Python. You can use Anaconda to have multiple Pythons (in multiple conda environments) besides the system Python. You just have to make sure which one is invoked when you run scripts and make sure it's the one you intended.
To answer the "literal" question you asked, you can specify the Python version when installing something:
conda install -c anaconda flask python=2
This will keep your Python at version 2 or report a mismatch if the package you want to install isn't available on anaconda for Python 2. The number of packages dropping Python 2 support is increasing because Python 2 is near it's "end of life", so don't expect to get latest or even near-latest releases of the packages when keeping at Python 2.
Personally I would recommend to create a different environment instead of trying to install to much into the base environment:
conda create -n mypython2environment python=2 flask
And by activating that environment you should be able to use the packages you installed in that environment:
activate mypython2environment
Several IDEs have built-in support for conda environments, so these may be helpful (especially in making sure you use the correct environment and thus the correct Python).
This just confuses me and I don't know what it means. I have 3.6.4 installed on my computer(MacOS) but it doesn't want to work.
I can't think of any solution and don't know what to do.
The answer is slightly different wether you are on a Mac or a Linux (I am not that used of Windows for Python working).
Install
(MacOS =>) Be sure that the XCode CLI tools are installed on your computer.
xcode-select --install
Then, to install the virtualenv, you have to enter the following command.
pyenv install 3.6.4
Here, you can have some issues regarding the zlib library that is not available. Nevertheless, the XCode CLI should have installed zlib. So you are good to go (it still has some issues on MacOS Mojave nevertheless).
Create Virtualenv
Then create a new virtualenv for a future use :
pyenv virtualenv 3.6.4 v3.6.4
Check
Check that everything is ok and that the virtualenv is installed through the following command :
pyenv virtualenvs
Use
Then you just have to use it. For instance for a local use :
pyenv local v3.6.4
Check
Check that everything is ok:
pyenv local
and it should show v3.6.4.
I am trying to start a Python 3.6 project by creating a virtualenv to keep the dependencies. I currently have both Python 2.7 and 3.6 installed on my machine, as I have been coding in 2.7 up until now and I wish to try out 3.6. I am running into a problem with the different versions of Python not detecting modules I am installing inside the virtualenv.
For example, I create a virtualenv with the command: virtualenv venv
I then activate the virtualenv and install Django with the command: pip install django
My problems arise when I activate either Python 2.7 or 3.6 with the commands
py -2 or py -3, neither of the interactive shells detect Django as being installed.
Django is only detected when I run the python command, which defaults to 2.7 when I want to use 3.6. Does anyone know a possible fix for this so I can get my virtualenv working correctly? Thanks! If it matters at all I am on a machine running Windows 7.
Create virtual environment based on python3.6
virtualenv -p python3.6 env36
Activate it:
source env36/bin/activate
Then the venv36 has been activated, venv36's pip is available now , you can install Django as usual, and the package would be stored under env36/lib/python3.6/site-packages:
pip install django
You have to select the interpreter when you create the virtualenv.
virtualenv --python=PYTHON36_EXE my_venv
Substitute the path to your Python 3.6 installation in place of PYTHON36_EXE. Then after you've activated, python executable will be bound to 3.6 and you can just pip install Django as usual.
The key is that pip installs things for a specific version of Python, and to a very specific location. Basically, the pip command in your virtual environment is set up specifically for the interpreter that your virtual environment is using. So even if you explicitly call another interpreter with that environment activated, it will not pick up the packages pip installed for the default interpreter.