On new Debian 12 Bookworm installs, when I try running pip3 install [something] (whether that's Ansible or some other Python tool), I get the following error message:

error: externally-managed-environment

× This environment is externally managed
╰─> To install Python packages system-wide, try apt install
    python3-xyz, where xyz is the package you are trying to
    install.

    If you wish to install a non-Debian-packaged Python package,
    create a virtual environment using python3 -m venv path/to/venv.
    Then use path/to/venv/bin/python and path/to/venv/bin/pip. Make
    sure you have python3-full installed.

    If you wish to install a non-Debian packaged Python application,
    it may be easiest to use pipx install xyz, which will manage a
    virtual environment for you. Make sure you have pipx installed.

    See /usr/share/doc/python3.11/README.venv for more information.

note: If you believe this is a mistake, please contact your Python installation or OS distribution provider. You can override this, at the risk of breaking your Python installation or OS, by passing --break-system-packages.
hint: See PEP 668 for the detailed specification.

The error message says you can pass in the flag --break-system-packages but that sounds terrifying. I just want pip to stop nagging me, but let me manage my system dependencies like I have for many years.

I think some Python developers really want people like me to use virtual environments, but that's way too much effort when I don't really care to do that, thankyouverymuch. If you want to use venv more power to you. I just like getting stuff done on my little servers.

So the solution for Debian 12, at least, is to delete the EXTERNALLY-MANAGED file in your system Python installation:

sudo rm -rf /usr/lib/python3.11/EXTERNALLY-MANAGED

Note that the python3.11 version number should match whatever you have installed—it was 3.11 at the time of this blog post's writing.

See this answer on Stack Overflow for more. Another interesting option is to install and use pipx, which does the grunt work of managing the venvs for you.