# Install virtualenv for Python 2.7 and create a sandbox called my27project:pip2.7 install virtualenvvirtualenv-2.7 my27project # Use the built-in pyvenv program in Python 3.3 to create a sandbox called my33project:pyvenv-3.3 my33project # Check the system Python interpreter version:python --version# This will show Python 2.6.6 # Activate the my27project sandbox and check the version of the default Python interpreter in it:source my27project/bin/activatepython --version# This will show Python 2.7.6deactivate # Activate the my33project sandbox and check the version of the default Python interpreter in it:source my33project/bin/activatepython --version# This will show Python 3.3.5deactivate

When you use virtualenv to create a sandbox it will automatically install setuptools and pip for you inside the sandbox. If you use pyvenv then you must do it yourself. You can reuse the ez_setup.py file you downloaded earlier and just run it after you activate your new sandbox.