pipコマンド実行時に出力されるメッセージ(2025.5.23)

code:error.txt

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/python3.12/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.

Python 3.12以降では PEP 668 が有効となり、 仮想環境の外でグローバルに pip3 install しようとすると多くの場合 error: externally-managed-environment と怒られる。 後述のvenvで仮想環境を作り、その中でpipを実行する。