How to use python venv with both site packages and pip?

Question

When I run python venv:

python -m venv test-env
. test-env/bin/activate

I have virtual environment with pip avaliable (although it's not avaliable for my outside the venv. However, in this environment all packages need to be installed, which are already avaliable globally. I learned I have to set venv with --system-site-packages flag. But when I do this:

python -m venv --system-site-packages test-env
. test-env/bin/activate

I can't use pip inside the virtual environment, so it's pointless, because I can't install any additional packages. How to solve this problem?

Where is this file? Should I use the `--system-site-packages` flag in this case? — Przemysław Czechowski, Jun 01 '18 at 11:16
https://pip.pypa.io/en/stable/user_guide/#requirements-files — bruno desthuilliers, Jun 01 '18 at 11:32

score 0 · Answer 1 · edited Feb 28 '20 at 02:45

I can't use pip inside the virtual environment, so it's pointless, because I can't install any additional packages. How to solve this problem?

A bit to early to give up on pip! You can add any package you want in the new environment, eg:

pip install pandas

Looks like you are unsure about a list of your dependencies. They are normally stored in a file called requirements.txt, which is specific to a project. For example, a github repository ususally has requirements.txt - so that users can replicate the dependcies.

You can create requirements.txt manually, or use pip freeze after you have installed the packages you want one by one. A bit more here.

Also recommended to look at pipenv, which combines virtualenv and pip functionality under one roof.

How to use python venv with both site packages and pip?

1 Answers1