PIP complains when I try to install a module into another virtualenv

I have a module installed in the main python install, however, I'd like to install t开发者_JAVA技巧his module into my virtualenv and I'd like it to be portable, how can I do that?

I'm getting this error:

(v_env)[nubela@nubela-desktop zine-ified]$ pip -E v_env install pyfacebook
Requirement already satisfied (use --upgrade to upgrade): pyfacebook in /home/nubela/...

To force pip installing a package when it's already been detected, you need to use the -I or --ignore-installed flag. In your case, the command would be:

pip -E v_env install -I pyfacebook

pip will then install it into your virtualenv.