Kind of similar to what rvm does:
pip install virtualenv cd my_project_folder virtualenv nameofenv source nameofenv/bin/activate
Now you should see a prefix on the shell prompt, with the name of the environment. Afterwards, do:
pip install somepackage
and it will install it for a specific package. To get something akin to a Gemfile.lock do:
pip freeze > requirements.txt
And to do a bundle install:
pip install -r requirements.txt