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 am on an Ubuntu machine, where Python 3.10 is automatically installed. To do a given task in a shared codebase I need to use Python 3.9 for some issues with new versions.
I would like to have both of the Python installed on my machine and be able to use both and switching if I need to.
So, I am trying to install old Python 3.9 with the command sudo apt-get install python3.9 and it succeeded in installation, but I can't find it anywhere even with which python3.9 and similar.
Even the python interpreter option in VSCode does not show it.
I think I am missing something. Can please someone help me? Thank you
Python should be installed under the /usr/bin/ folder. If it's not there, you might have not actually installed the package.
Check out this guide for installing specific versions (Scroll down to the "Use Deadsnakes PPA to Install Python 3 on Ubuntu" section.)
This will allow you to install specific version of python like python3.9
Packages on Ubuntu (usually executables) are installed in the /usr/bin directory. You could try to list all executables under /usr/bin with
ls /usr/bin/python*
This is the easiest way. You could see also what packages are installed
apt list --installed | grep python
Suddenly I cannot run ansible.
Whenever I try any ansible command like ansible-playbook, ansible version, etc. it shows error
`/Users/myusername/Library/Python/2.7/bin/ansible: /System/Library/Frameworks/Python.framework/Versions/2.7/Resources/Python.app/: bad interpreter: No such file or directory`,
Even if I let ansible run different python version, like ansible-playbook --version -e 'ansible_python_interpreter=/usr/bin/python3, it shows the same error.
FYI: which ansible returns /Users/myusername/Library/Python/2.7/bin/ansible
I guess it is related to my recent installation of python. Since I installed a python3.10 recently, The python2.7 becomes not work. Note I did not remove anything about python2.7 myself. looks like the installation of python3.10 changed python2.7 setting.
For most other application, I now pointed the system to use python3 as workaround, e.g. I set CLOUDSDK_PYTHON=/usr/bin/python3 to make accessing cloud cli works again. But for Ansible, I have not figured out how to make it work. I am using MacOS terminal.
Does anybody know how to resolve the above issue so that I can run ansible again? Anyway is OK as long as I can run ansible. Either reinstall ansible and let it use python3 instead of using Python2.7 or guide me how to reinstall python2.7 (in a right way, not messy with python3.10, currently I am scared of installing python, I am afraid if I reinstall python2.7, both python3.10 and 2.7 will be out of work then I cannot work).
Please help. Thanks.
You will have to do some cleanup on your system because somehow, Python 2.7 was removed from you system. This might have happened due to updating to macos 12.4 Monterey at some point, because Monterey 12.3 and newer removed the system-provided Python 2.7, replacing it with a Python 3.8.9 installation (/usr/bin/python3).
However, you still have stuff in your environment that reference all those Python 2.7 things, like your ${HOME}/Library/Python/2.7/bin/ansible directory.
Here are the things you can do to (hopefully) make ansible and your environment work again.
Change your shell's PATH environment.
You're probably using zsh since it's the default shell on macos. Have you ever changed your .zshrc or other environment files to add /Users/<name>/Library/Python/2.7/bin in your PATH? You will need to remove that.
Additionally, if you strictly want to use the Python 3.10 you manually installed (and not Monterey's system-provided /usr/bin/python3 which is python v3.8.9), you will probably need a PATH that looks like this...
# somewhere in your ~/.zshrc, probably near the bottom
export PATH="/Library/Frameworks/Python.framework/Versions/3.10/bin:${PATH}"
Re-install Ansible
With whatever python3 binary you're using, re-install ansible
python3 -m pip install --user ansible
This will end up installing ansible into ${HOME}/Library/Python/<VERSION>/bin
Update PATH again to include new bin dir
Building on part (1) above, you want to include the bin directory for Python stuff in your user directory, to be able to refer to anything installed by pip install --user.
# somewhere in your ~/.zshrc, probably near the bottom
export PATH="${HOME}/Library/Python/3.10/bin:${PATH}"
export PATH="/Library/Frameworks/Python.framework/Versions/3.10/bin:${PATH}"
Reload your shell and try to run ansible
# if you already have a shell open, run this
# to reload your zsh configs
exec zsh
# hopefully this returns the correct path!
which ansible
# and hopefully this runs!
ansible --help
Reinstall Anything Else You Need
You reference stuff like CLOUDSDK_PYTHON which sounds like you also have stuff like the gcloud module installed. Time to reinstall those with your new Python.
python3 -m pip install --user gcloud
# and whatever else needs reinstalling
Hopefully this all fixes your environment. Now you can clean up the remnants of Python 2.7 stuff from your home directory once everything else is working, as this directory has broken module installs that reference a deleted system Python anyway.
cd ~/Library/Python
rm -rf 2.7
[On a mac]
I know I can get packages doing pip install etc.
But I'm not entirely sure how all this works.
Does it matter which folder my terminal is in when I write this command?
What happens if I write it in a specific folder?
Does it matter if I do pip/pip3?
I'm doing a project, which had a requirements file.
So I went to the folder the requirements txt was in and did pip install requirements, but there was a specific tensorflow version, which only works for python 3.7. So I did """python3.7 -m pip install requirements""" and it worked (i'm not sure why). Then I got jupyter with brew and ran a notebook which used one of the modules in the requirements file, but it says there is no such module.
I suspect packages are linked to specific versions of python and I need to be running that version of python with my notebook, but I'm really not sure how. Is there some better way to be setting up my environment than just blindley pip installing stuff in random folders?
I'm sorry if this is not a well formed question, I will fix it if you let me know how.
Yes, there is. Setup an virtual environment.
pip install virtualenv #installs the library
virtualenv mypython #creates the environment
source mypython/bin/activate #activates the environment
Now, install your requirements through pip.
Afterwards, when your work is finished.
Just type deactivate to come out of the virtual environment.
There may be a difference between pip and pip3, depending on what you have installed on your system. pip is likely the pip used for python2 while pip3 is used for python3.
The easiest way to tell is to simply execute python and see what version starts. python will run typically run the older version 2.x python and python3 is required to run python version 3.x. If you install into the python2 environment (using pip install or python -m pip install the libraries will be available to the python version that runs when you execute python. To install them into a python3 environment, use pip3 or python3 -m pip install.
Basically, pip is writing module components into a library path, where import <module> can find them. To do this for ALL users, use python3 or pip3 from the command line. To test it out, or use it on an individual basis, use a virtual environment as #Abhishek Verma said.
I have a Python 2.7.11 installed on one of my LAB stations. I would like to upgrade Python to at least 3.5.
How should I do that ?
Should I prefer to completely uninstall 2.7.11 and than install the new one ?
Is there a way to update it ? Is an update a good idea ?
Every minor version of Python, that is any 3.x and 2.x version, will install side-by-side with other versions on your computer. Only patch versions will upgrade existing installations.
So if you want to keep your installed Python 2.7 around, then just let it and install a new version using the installer. If you want to get rid of Python 2.7, you can uninstall it before or after installing a newer version—there is no difference to this.
Current Python 3 installations come with the py.exe launcher, which by default is installed into the system directory. This makes it available from the PATH, so you can automatically run it from any shell just by using py instead of python as the command. This avoids you having to put the current Python installation into PATH yourself. That way, you can easily have multiple Python installations side-by-side without them interfering with each other. When running, just use py script.py instead of python script.py to use the launcher. You can also specify a version using for example py -3 or py -3.6 to launch a specific version, otherwise the launcher will use the current default (which will usually be the latest 3.x).
Using the launcher, you can also run Python 2 scripts (which are often syntax incompatible to Python 3), if you decide to keep your Python 2.7 installation. Just use py -2 script.py to launch a script.
As for PyPI packages, every Python installation comes with its own folder where modules are installed into. So if you install a new version and you want to use modules you installed for a previous version, you will have to install them first for the new version. Current versions of the installer also offer you to install pip; it’s enabled by default, so you already have pip for every installation. Unless you explicitly add a Python installation to the PATH, you cannot just use pip though. Luckily, you can also simply use the py.exe launcher for this: py -m pip runs pip. So for example to install Beautiful Soup for Python 3.6, you could run py -3.6 -m pip install beautifulsoup4.
If you are upgrading any 3.x.y to 3.x.z (patch) Python version, just go to Python downloads page get the latest version and start the installation. Since you already have Python installed on your machine installer will prompt you for "Upgrade Now". Click on that button and it will replace the existing version with a new one. You also will have to restart a computer after installation.
If you are upgrading from 3.x to 3.y (minor) then you will be prompted with "Install Now". In this case, you are not upgrading, but you are installing a new version of Python. You can have more than one version installed on your machine. They will be located in different directories. When you have more than one Python version on your machine you will need to use py lanucher to launch a specific version of Python.
For instance:
py -3.7
or
py -3.8
Make sure you have py launcher installed on your machine. It will be installed automatically if you are using default settings of windows installer. You can always check it if you click on "Customize installation" link on the installation window.
If you have several Python versions installed on your machine and you have a project that is using the previous version of Python using virtual environment e.g. (venv) you can upgrade Python just in that venv using:
python -m venv --upgrade "your virtual environment path"
For instance, I have Python 3.7 in my ./venv virtual environment and I would like upgrade venv to Python 3.8, I would do following
python -m venv --upgrade ./venv
Installing/Upgrading Python Using the Chocolatey Windows Package Manager
Let's say you have Python 2.7.16:
C:\Windows\system32>python --version
python2 2.7.16
...and you want to upgrade to the (now current) 3.x.y version. There is a simple way to install a parallel installation of Python 3.x.y using a Windows package management tool.
Now that modern Windows has package management, just like Debian Linux distributions have apt-get, and RedHat has dnf: we can put it to work for us! It's called Chocolatey.
What's Chocolatey?
Chocolatey is a scriptable, command line tool that is based on .NET 4.0 and the nuget package manager baked into Visual Studio.
If you want to learn about Chocolatey and why to use it, which some here reading this might find particularly useful, go to https://chocolatey.org/docs/why
Installing Chocolatey
To get the Chocolatey Package Manager, you follow a process that is described at https://chocolatey.org/docs/installation#installing-chocolatey,
I'll summarize it for you here. There are basically two options: using the cmd prompt, or using the PowerShell prompt.
CMD Prompt Chocolatey Installation
Launch an administrative command prompt. On Windows 10, to do this:
Windows + R
Type cmd
Press Ctrl + ⇧ Shift + ↵ Return
If you don't have administrator rights on the system, go to the Chocolatey website. You may not be completely out of luck and can perform a limited local install, but I won't cover that here.
Copy the string below into your command prompt and type Enter:
#"%SystemRoot%\System32\WindowsPowerShell\v1.0\powershell.exe" -NoProfile -InputFormat None -ExecutionPolicy Bypass -Command "iex ((New-Object System.Net.WebClient).DownloadString('https://chocolatey.org/install.ps1'))" && SET "PATH=%PATH%;%ALLUSERSPROFILE%\chocolatey\bin"
Chocolatey will be downloaded and installed for you as below:
Getting latest version of the Chocolatey package for download.
Getting Chocolatey from https://chocolatey.org/api/v2/package/chocolatey/0.10.11.
Downloading 7-Zip commandline tool prior to extraction.
Extracting C:\Users\blahblahblah\AppData\Local\Temp\chocolatey\chocInstall\chocolatey.zip to C:\Users\blahblahblah\AppData\Local\Temp\chocolatey\chocInstall...
Installing chocolatey on this machine
Creating ChocolateyInstall as an environment variable (targeting 'Machine')
Setting ChocolateyInstall to 'C:\ProgramData\chocolatey'
WARNING: It's very likely you will need to close and reopen your shell
before you can use choco.
Restricting write permissions to Administrators
We are setting up the Chocolatey package repository.
The packages themselves go to 'C:\ProgramData\chocolatey\lib'
(i.e. C:\ProgramData\chocolatey\lib\yourPackageName).
A shim file for the command line goes to 'C:\ProgramData\chocolatey\bin'
and points to an executable in 'C:\ProgramData\chocolatey\lib\yourPackageName'.
Creating Chocolatey folders if they do not already exist.
WARNING: You can safely ignore errors related to missing log files when
upgrading from a version of Chocolatey less than 0.9.9.
'Batch file could not be found' is also safe to ignore.
'The system cannot find the file specified' - also safe.
chocolatey.nupkg file not installed in lib.
Attempting to locate it from bootstrapper.
PATH environment variable does not have C:\ProgramData\chocolatey\bin in it. Adding...
WARNING: Not setting tab completion: Profile file does not exist at 'C:\Users\blahblahblah\Documents\WindowsPowerShell\Microsoft.PowerShell_profile.ps1'.
Chocolatey (choco.exe) is now ready.
You can call choco from anywhere, command line or powershell by typing choco.
Run choco /? for a list of functions.
You may need to shut down and restart powershell and/or consoles
first prior to using choco.
Ensuring chocolatey commands are on the path
Ensuring chocolatey.nupkg is in the lib folder
Either Exit the CMD prompt or type the following command to reload the environment variables:
refreshenv
PowerShell Chocolatey Installation
If you prefer PowerShell to the cmd prompt, you can do this directly from there, however you will have to tell PowerShell to run with a proper script execution policy to get it to work. On Windows 10, the simplest way I have found to do this is to type the following into the Cortana search bar next to the Windows button:
PowerShell.exe
Next, right click on the 'Best Match' choice in the menu that pops up and select 'Run as Administrator'
Now that you're in PowerShell, hopefully running with Administrator privileges, execute the following to install Chocolatey:
Set-ExecutionPolicy Bypass -Scope Process -Force; iex ((New-Object System.Net.WebClient).DownloadString('https://chocolatey.org/install.ps1'))
PowerShell will download Chocolatey for you and launch the installation. It only takes a few moments. It looks exactly like the CMD installation, save perhaps some fancy colored text.
Either Exit PowerShell or type the following command to reload the environment variables:
refreshenv
Upgrading Python
The choco command is the same whether you use PowerShell or the cmd prompt. Launch your favorite using the instructions as above. I'll use the administrator cmd prompt:
C:\WINDOWS\system32>choco upgrade python -y
Essentially, chocolatey will tell you "Hey, Python isn't installed" since you're coming from 2.7.x and it treats the 2.7 version as completely separate. It is only going to give you the most current version, 3.x.y (as of this writing, 3.7.2, but that will change in a few months):
Chocolatey v0.10.11
Upgrading the following packages:
python
By upgrading you accept licenses for the packages.
python is not installed. Installing...
python3 v3.x.y [Approved]
python3 package files upgrade completed. Performing other installation steps.
Installing 64-bit python3...
python3 has been installed.
Installed to: 'C:\Python37'
python3 can be automatically uninstalled.
Environment Vars (like PATH) have changed. Close/reopen your shell to
see the changes (or in powershell/cmd.exe just type `refreshenv`).
The upgrade of python3 was successful.
Software installed as 'exe', install location is likely default.
python v3.x.y [Approved]
python package files upgrade completed. Performing other installation steps.
The upgrade of python was successful.
Software install location not explicitly set, could be in package or
default install location if installer.
Chocolatey upgraded 2/2 packages.
See the log for details (C:\ProgramData\chocolatey\logs\chocolatey.log).
Either exit out of the cmd/Powershell prompt and re-enter it, or use refreshenv then type py --version
C:\Windows\System32>refreshenv
Refreshing environment variables from registry for cmd.exe. Please wait...Finished..
C:\Windows\system32>py --version
Python 3.7.2
Note that the most recent Python install will now take over when you type Python at the command line. You can run either version by using the following commands:
py -2
Python 2.7.16 (v2.7.16:413a49145e, Mar 4 2019, 01:37:19) [MSC v.1500 64 bit (AMD64)] on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> exit()
C:\>py -3
Python 3.7.2 (tags/v3.7.2:9a3ffc0492, Dec 23 2018, 23:09:28) [MSC v.1916 64 bit (AMD64)] on win32
Type "help", "copyright", "credits" or "license" for more information.
>>>exit()
C:\>
From here I suggest you use the Python pip utility to install whatever packages you need. For example, let's say you wanted to install Flask. The commands below first upgrade pip, then install Flask
C:\>py -3 -m pip install --upgrade pip
Collecting pip
Downloading https://files.pythonhosted.org/packages/d8/f3/413bab4ff08e1fc4828dfc59996d721917df8e8583ea85385d51125dceff/pip-19.0.3-py2.py3-none-any.whl (1.4MB)
100% |████████████████████████████████| 1.4MB 1.6MB/s
Installing collected packages: pip
Found existing installation: pip 18.1
Uninstalling pip-18.1:
Successfully uninstalled pip-18.1
Successfully installed pip-19.0.3
c:\>py -3 -m pip install Flask
...will do the trick. Happy Pythoning!
A quick and painless way for me was to do the following:
Do a pip freeze > requirements.txt on my affected environments (or whatever method you want for backing up your requirements)
Remove the Old version of Python (in my case it was 3.8)
Remove the associated environments
Install the new version (3.9.5 in my case)
Recreate my environments python -m venv venv or however you wish
Reinstall my plug-ins/apps pip install -r requirements.txt or however you wish
Python 2.x and Python 3.x are different. If you would like to download a newer version of Python 2, you could just download and install the newer version.
If you want to install Python 3, you could install Python 3 separately then change the path for Python 2.x to Python 3.x in Control Panel > All Control Panel Items > System > Advanced System Settings > Environment Variables.
In 2019, you can install using chocolatey. Open your cmd or powershell, type:
choco install python
Nowadays you can just install several Python versions from Microsoft Store. Those are published there by Python Software Foundation.
https://apps.microsoft.com/store/search?hl=en-en&gl=EN&publisher=Python%20Software%20Foundation
Just install python newest version's installer it will automatically detect your python version and will say upgrade python and starts upgrading
I was able to execute PowerShell with the following command and python upgraded with no issue. python -m pip install --upgrade pip please see image
You can use pyenv. It let you easily switch between all versions of python.