migrate python project from Windows virtualenv to Linux virtualenv

cross-platform-interface-for-virtualenv

from: http://stackoverflow.com/questions/12033861/cross-platform-interface-for-virtualenv

On Windows:
using virtualenv as source:
    pip freeze > requirements.txt

Linux:
    virtualenv --no-site-packages prod_env
    source prod_env/bin/activate
    pip install -r requirements.txt

When you have a requirements change: 
simply regenerate the requirements.txt file and run pip install -r requirements.txt in production.

don't have access to the Internet:
    create your own private pypi server and push your packages there.