Hi all, I was reading the documentation of distutils, setuptools and distribution cause I was searching for a way to add some optional dependancies to a project. In fact i would like to add an optional dependency and it will change some components of the a module. I'll explain a little bit more: I have a module called "storelocator", when you have use it without any optional dependency. In the setup script I have the following option: extras_require = { "satchmo" : ["Satchmo"], } If you install the package with the satchmo support like that: storelocator[satchmo] Then I would like be able with pkg_resources or something like to check in the code if the satchmo support has been enabled or not, if yes, i'll change some part of my package or not. Mathieu Leduc-Hamel