virtualenv is a tool that creates sandboxed Python environments.
virtualenv allows you to create a sandboxed and isolated environment where Python packages can be installed without interfering with other packages on the same machine. With several virtualenvs, many different pieces of Python software with different and even mutually exclusive dependencies can coexist together.
$ virtualenv ENV $ source ENV/bin/activate (ENV) $ easy_install (package) (ENV) $ deactivate $ ...
A virtualenv can also be set up to completely ignore the system's site packages, to ensure that all dependencies are installed within the virtualenv sandboxed environment.
$ virtualenv ENV --no-site-packages