Common installation tools such as ``Setuptools`` and ``pip`` work as
expected with venvs - i.e. when a venv is active, they install Python
packages into the venv without needing to be told to do so explicitly.
- Of course, you need to install them into the venv first: this could be
- done by running ``ez_setup.py`` with the venv activated,
- followed by running ``easy_install pip``. Alternatively, you could download
- the source tarballs and run ``python setup.py install`` after unpacking,
- with the venv activated.
When a venv is active (i.e. the venv's Python interpreter is running), the
attributes :attr:`sys.prefix` and :attr:`sys.exec_prefix` point to the base