Python structure question

[PickyBiker]

I'm struggling with the overall structure of a python program. The following code works (as-is), but I'm not sure this is the way to let a main program function access class elements. If I move the class Test to a test.py file and then import that file it doesn't work so there must be a better way.

The import being used is: import test

What am I doing wrong?

class Test(object):
    def __init__ (self):
        pass
    class a(object):
        def __init__ (self):
            print("a")
    class b(object):
        def __init__ (self):
            print("b")

def    main():
    t = Test()
    t.a()
    t.b()
    print("Done")

if __name__=="__main__":
    main()