[Distutils] What's the Distutils/setuptools api to install an .egg?

Hi All, What's the distutils api call that I need to make to install an .egg. At the moment I'm using easy_install and the command line but under vista it requires escalated privilages. There must be a "batteries-included" way within python either in setuptools or distutils to install an .EGG from pypi? That is without telling the users that they must download either easy_install or pip before they can do the .egg install. Thanks in advance David