(sisyphus-game)prosaur@prosaur:~$ virtualenv venv/testenv
New python executable in venv/testenv/bin/python2.7
Also creating executable in venv/testenv/bin/python
Installing setuptools............done.
Installing pip...............done.
(sisyphus-game)prosaur@prosaur:~$ ~/venv/testenv/bin/pip install Twisted
Requirement already satisfied (use --upgrade to upgrade): Twisted in /usr/local/python2.7/lib/python2.7/site-packages/Twisted-10.1.0-py2.7-linux-x86_64.egg
Requirement already satisfied (use --upgrade to upgrade): zope.interface in /usr/local/python2.7/lib/python2.7/site-packages/zope.interface-3.6.1-py2.7-linux-x86_64.egg (from Twisted)
Requirement already satisfied (use --upgrade to upgrade): setuptools in /usr/local/python2.7/lib/python2.7/site-packages/setuptools-0.6c11-py2.7.egg (from zope.interface->Twisted)
Cleaning up...