For Windows 10, I think this is what you are looking for a list of available installed Pythons. This is different from a list of packages as you can see below. Also, on Ubuntu 20.04, I think the command is Python3 -0 list
.
Yes, this works similar to node version manager.
c:\Users\user\AppData\Local\Programs\Python>py -0 list
Python 0 not found!
Installed Pythons found by py Launcher for Windows
-3.10-64 *
-3.9-64
-3.7-64
-3.6-64
-2.7-64
Requested Python version (0) not installed, use -0 for available pythons
c:\Users\user\AppData\Local\Programs\Python>py -0p
Installed Pythons found by py Launcher for Windows
-3.10-64 C:\Python310\python.exe *
-3.9-64 C:\Users\user\AppData\Local\Programs\Python\Python39\python.exe
-3.7-64 C:\Program Files (x86)\Microsoft Visual Studio\Shared\Python37_64\python.exe
-3.6-64 C:\Program Files (x86)\Microsoft Visual Studio\Shared\Python36_64\python.exe
-2.7-64 C:\Python27amd64\python.exe
See: https://www.infoworld.com/article/3617292/how-to-use-pythons-py-launcher-for-windows.html
See Also: https://www.freecodecamp.org/news/manage-multiple-python-versions-and-virtual-environments-venv-pyenv-pyvenv-a29fb00c296f/
From the above link, "If you wish to use multiple versions of Python on a single machine, then pyenv is a commonly used tool to install and switch between versions. This is not to be confused with the previously mentioned depreciated pyvenv script. It does not come bundled with Python and must be installed separately." -- Note: This acts similar to Node Version Manager with versions of Node.js and NPM.
See Also: https://github.com/pyenv-win/pyenv-win#installation
Action: Open PowerShell and type the following web request. The link above offers other approaches as well, but this appears to be the easiest approach. The name of the runtime output file is not a name variant like 'pyenv-win' but actually 'pyenv', as originally expected.
PS C:\Users\user> Invoke-WebRequest -UseBasicParsing -Uri "https://raw.githubusercontent.com/pyenv-win/pyenv-win/master/pyenv-win/install-pyenv-win.ps1" -OutFile "./install-pyenv-win.ps1"; &"./install-pyenv-win.ps1"
pyenv-win 2.64.11 installed.
No updates available.
PS C:\Users\user>
Example Output for working with 'pyenv', Python's Version Manager.
C:\Users\user>pyenv --version
pyenv 2.64.11
C:\Users\name>pyenv
pyenv 2.64.11
Usage: pyenv <command> [<args>]
Some useful pyenv commands are:
commands List all available pyenv commands
duplicate Creates a duplicate python environment
local Set or show the local application-specific Python version
global Set or show the global Python version
shell Set or show the shell-specific Python version
install Install a Python version using python-build
uninstall Uninstall a specific Python version
update Update the cached version DB
rehash Rehash pyenv shims (run this after installing executables)
vname Show the current Python version
version Show the current Python version and its origin
version-name Show the current Python version
versions List all Python versions available to pyenv
exec Runs an executable by first preparing PATH so that the selected Python
which Display the full path to an executable
whence List all Python versions that contain the given executable
See `pyenv help <command>' for information on a specific command.
For full documentation, see: https://github.com/pyenv-win/pyenv-win#readme
C:\Users\name>pyenv commands
--version
commands
duplicate
exec
export
global
help
install
local
rehash
shell
shims
uninstall
update
version-name
version
versions
vname
whence
which
C:\Users\name>pyenv version
No global python version has been set yet. Please set the global version by typing:
pyenv global 3.7.2
C:\Users\user>pyenv local
no local version configured for this directory
C:\Users\user>pyenv global
no global version configured
C:\Users\user>pyenv local 3.9-64
pyenv specific python requisite didn't meet. Project is using different version of python.
Install python '3.9-64' by typing: 'pyenv install 3.9-64'
My Note: Version name from 'https://www.python.org/downloads/' is different to those provided by 'pyenv'. This version was already installed locally, but it is outside the control of this Python version manager, so it is not visible to the manager.
C:\Users\user>pyenv install 3.8.10-64
:: [Info] :: Mirror: https://www.python.org/ftp/python
pyenv-install: definition not found: local
My Note(s): This Python version is not part of the managed list although this version exists at 'https://www.python.org/downloads/'. So you must see the list provided by the manager. See all available versions with `pyenv install --list'.
C:\Users\user>pyenv install --list
Note: Review the list from this call and make your selection.
C:\Users\user>pyenv install 3.8.10
:: [Info] :: Mirror: https://www.python.org/ftp/python
:: [Downloading] :: 3.8.10 ...
:: [Downloading] :: From https://www.python.org/ftp/python/3.8.10/python-3.8.10-amd64-webinstall.exe
:: [Downloading] :: To C:\Users\user\.pyenv\pyenv-win\install_cache\python-3.8.10-amd64-webinstall.exe
:: [Installing] :: 3.8.10 ...
:: [Info] :: completed! 3.8.10
My Note(s): With this Python version manager, 'pyenv', following installation, it appears that one must designate the version as 'local' or 'global' after the installation which would follow the same paradigm as the Node.js Version Manager (NVM). Again, from what I can see, the Python version manager can only see what versions of Python the manager installs; and it can only uninstall a version it has installed with the Python version manager.
C:\Users\user>pyenv local 3.8.10
C:\Users\user>pyenv local
3.8.10
C:\Users\user>pyenv version
3.8.10 (set by C:\Users\user\.python-version)
C:\Users\user>pyenv versions
* 3.8.10 (set by C:\Users\user\.python-version)
C:\Users\user>pyenv vname
3.8.10
C:\Users\user>pyenv global
no global version configured
The following below is for working with packages.
See Also: https://www.freecodecamp.org/news/manage-multiple-python-versions-and-virtual-environments-venv-pyenv-pyvenv-a29fb00c296f/
From the above link, "When the environment is active, any packages can be installed to it via pip as normal. By default, the newly created environment will not include any packages already installed on the machine. As pip itself will not necessarily be installed on the machine. It is recommended to first upgrade pip to the latest version, using 'pip install --upgrade pip'." -- I performed the pip upgrade just before making these two calls to list the packages and their versions below.
c:\Users\user\AppData\Local\Programs\Python>pip list
Package Version
---------- -------
pip 22.1
setuptools 62.2.0
wheel 0.37.1
c:\Users\user\AppData\Local\Programs\Python>pip list --local
Package Version
---------- -------
pip 22.1
setuptools 62.2.0
wheel 0.37.1