virtualenv --no-site-packages and pip still finding global packages?

user_104986 0
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I was under the impression that virtualenv --no-site-packages would create a completely separate and isolated Python environment, but it doesn't seem to.

For example, I have python-django installed globally, but wish to create a virtualenv with a different Django version.

$ virtualenv --no-site-packages foo       
New python executable in foo/bin/python
Installing setuptools............done.
$ pip -E foo install Django
Requirement already satisfied: Django in /usr/share/pyshared
Installing collected packages: Django
Successfully installed Django

From what I can tell, the pip -E foo install above is supposed to re-install a new version of Django. Also, if I tell pip to freeze the environment, I get a whole lot of packages. I would expect that for a fresh environment with --no-site-packages this would be blank?

$ pip -E foo freeze
4Suite-XML==1.0.2
BeautifulSoup==3.1.0.1
Brlapi==0.5.3
BzrTools==1.17.0
Django==1.1
... and so on ...

Am I misunderstanding how --no-site-packages is supposed to work?

pip virtualenv python
14 Answers

Temporarily clear the PYTHONPATH with:

export PYTHONPATH=

Then create and activate the virtual environment:

virtualenv foo
. foo/bin/activate

Only then:

pip freeze
user_88448910

I came accross the same problem where pip in venv still works as global pip.
After searching many pages, i figure it out this way.
1. Create a new venv by virtualenv with option "--no-site-packages"

virtualenv --no-site-packages --python=/xx/xx/bin/python my_env_nmae

please note that although the "--no-site-packages" option was default true since 1.7.0 in the doc file of virtualenv, but i found it not working unless you set it on manually. In order to get a pure venv, i strongly suggest turning this option on 2. Activate the new env you created

source ./my_env_name/bin/activate
  1. Check your pip location and python location and make sure these two commands are under virtual envirement
pip --version
which python
  1. Use pip under virtual env to install packages free from the global packages interuption
pip install package_name

Wish this answer helps you!

user_67242650

My problem was the pip and python3 versions. For the latest version of django installation, pip3 is necessary. So my problem was solved after creating the virtual environment using the following commands:

> virtualenv --python=python3 venv
> source venv/bin/activate
> which pip3 #should be different from /usr/local/bin/pip3
...<some-directory>/venv/bin/pip3

PS This problem occurred because the default version of my python in ubuntu was 2.7. By using the above command it would ignore the default version.

user_73100770

for anyone updated to ubuntu 22.04 or confused by the same problem, remove the installed pip first, re-install the pip to /usr/local/bin, according to the doc in python.org, by the time is 3.10.5, run:

sudo python get-pip.py --prefix=/usr/

you need to download the script if you don't have one.After success message return, install virtualenv or poetry, it would notice you that /usr/local is not writable, and would install to ~/.local/what/ever, that' fine. And then everything is good to go, use virtualenv to re-create the venv folder in your project dir. if anything strange happend, use which command to check the path of pip3 or virtualenv, and remove them.

user_193841880
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