Debian Stable wants me to install Python modules using pipx. So I do
pipx install auditwheel
pipx ensurepath
python3 -m pipx ensurepath
python3
Output:
Python 3.11.2 (main, Mar 13 2023, 12:18:29) [GCC 12.2.0] on linux
Type "help", "copyright", "credits" or "license" for more information.
And:
import auditwheel
Output:
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
ModuleNotFoundError: No module named 'auditwheel'
What am I doing wrong?
From Python 3.11 onward, Debian encourages the users to create a separate Python virtual environment to install Python packages.
Because Debian declares its Python install to be externally-managed, pip (and other installers) will refuse to install packages system-wide. Installation is only possible in virtual environments or separate Python installs.
This is because Python package installers (like pip) are unaware of the constraints that APT-managed packages have on libraries and versions. See PEP 668 for a full discussion of the problems that can occur when multiple installers operate on the same Python install.
Therefore, the optimal way is to create a virtual environment, say MyEnv, and install packages therein:
mkdir -p $HOME/.venvs # Create a folder for all virtual environments
python3 -m venv $HOME/.venvs/MyEnv # Create MyEnv
This will create a directory $HOME/.venvs/MyEnv with a configuration file pyvenv.cfg which includes some details for this virtual environment, such as the Python executable and Python version.
Verify the version of the Python in the virtual environment:
$HOME/.venvs/MyEnv/bin/python --version
The executables of the created virtual environment are found under $HOME/.venvs/MyEnv/bin.
To install a package into the virtual environment, use
$HOME/.venvs/MyEnv/bin/python -m pip install <some-package>
To 'activate' the virtual environment, i.e. adding its configuration variables into the shell environment, use
source $HOME/.venvs/MyEnv/bin/activate
Consult Python's guide to virtualenv and pip at Install packages in a virtual environment using pip and venv.
pipx manages virtual environments, but in a way that is not suitable for OP's purposes.The message in pip3 might be misleading when it comes to pipx as it is there mainly to get binaries produced by Python packages into ~/.local/bin and not to system-wide location.
You can still use pipx for single package, it creates virtual environment for each package installed. You can run, e.g.,
~/.local/pipx/venvs/PACKAGENAME/bin/python3
If you are OK with doing what Debian developers don't want and the level of isolation to install additional packages to user directory is sufficient for you, the easiest is to
pip3 install --break-system-packages --user package
To clarify use cases
pipx
You want yt-dlp package and you are not exactly interested in importing it when programming yourself in python but you are only interested in the binary it builds. So you do
pipx install yt-dlp and you can use yt-dlp binary.
pip, pip3
Your Python code is dependent on the package bitcash not available as a system package. You then run pip install bitcash # pip3 if pip is Python 2 on your system``.
The man page say: On Debian, pip is the command to use when installing packages for Python 2, while pip3 is the command to use when installing packages for Python 3. It has some "clever functions" s.t. pip provides pip3 functionality when there is no python2 installed. That might be bit confusing.
pip vs pip3 vs pipx? I find this extremely confusing.pipx is not exactly the same as pip.
pipx installs applications in an isolated environment. It will not help if you want to compile and import a module. You can use a virtual environment as AlQuemist suggests.
pipx; it isn't the right tool for your purposes."Debian documentation is at 5.2.2. Python Interpreters marked externally-managed:
If you need to install a Python application (or version) that isn't packaged in Debian, we recommend that you install it with pipx (in the pipx Debian package). pipx will set up an environment isolated from other applications and system Python modules, and install the application and its dependencies into that.
Emphasis mine, the docs do talk about application and under that paragraph is second one pointing to installing packages to the virtual environment;
If you need to install a Python library module (or version) that isn't packaged in Debian, we recommend installing it into a virtualenv, where possible. You can create virtualenvs with the venv Python stdlib module (in the python3-venv Debian package) or the virtualenv Python 3rd-party tool (in the virtualenv Debian package). For example, instead of running pip install --user foo, run: mkdir -p ~/.venvs && python3 -m venv ~/.venvs/foo && ~/.venvs/foo/bin/python -m pip install foo to install it in a dedicated virtualenv.
For which AlQuemist's answer also highlights...
pipinstead ofpipxand check out how to utilize virtual environments.pipxis for installing applications, not libraries.