Common convention for invoking unit tests across a python project?

Is there a standard convention, or even a growing one, around where and how to invoke the tests associated with a project? In many projects, I'm seeing it bundled into a Make, a separate test.py script at the top level of开发者_StackOverflow中文版 the project, etc to do the work. 

I looked around for some common thing with setup.py, but didn't spot anything there (granted, I didn't look hard). What's common and best practice?

The short answer is yes, there's a simple convention built-in to the unittest module. See this previous question.