What does pip install -e mean?

Question

Python

I'm learning flask from the tutorial and there are lines about installing dependencies:
pip install -e .
pip install '.[test]'
I haven't seen this installation method before.
What does it mean?
Installing modules from listed packages in code?

Answer 1

This key means that the package will be installed in editable mode:
-e, --editable Install a project in editable mode (ie setuptools "develop mode") from a local project path or a VCS url.
This is necessary if we want to edit the sources of the package we are installing.
This will place the package not in the usual site-packages directory, but in the current or specified directory. The paths to find the installed package will be added to the environment variable and python will easily find the installed library despite its unusual location.
You can find it like this:
pip install --help