环境：Mac、Python3.12.x版本（3.12.5）

问题：执行pip install xyz 后出现异常：

error: externally-managed-environment

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

If you wish to install a Python library that isn't in Homebrew,
use a virtual environment:

python3 -m venv path/to/venv
source path/to/venv/bin/activate
python3 -m pip install xyz

If you wish to install a Python application that isn't in Homebrew,
it may be easiest to use 'pipx install xyz', which will manage a
virtual environment for you. You can install pipx with

brew install pipx

You may restore the old behavior of pip by passing
the '--break-system-packages' flag to pip, or by adding
'break-system-packages = true' to your pip.conf file. The latter
will permanently disable this error.

If you disable this error, we STRONGLY recommend that you additionally
pass the '--user' flag to pip, or set 'user = true' in your pip.conf
file. Failure to do this can result in a broken Homebrew installation.

Read more about this behavior here: <https://peps.python.org/pep-0668/>

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.

-------------------------------------------------------

解决方法：
删除对应目录下的 EXTERNALLY-MANAGED 这个文件即可：

which python3 找到python的目录然后进入子目录：3.12.5/Frameworks/Python.framework/Versions/3.12/lib/python3.12

cd /usr/local/Cellar/python@3.12/3.12.5/Frameworks/Python.framework/Versions/3.12/lib/python3.12
rm -r EXTERNALLY-MANAGED

注意：如果担心直接删除导致环境异常，可以先将该文件移走
再次执行 pip3 install xyz 即可