services.keys()
simply returns a list. Setting the first element of that list to anything will have no effect.
I expect you want to do services[services.keys()[0]] = services.values()[0]
, although I can't imagine what you are trying to do with that code.
Edit
OK, I think I understand what you want to do. It seems that CherryPy relies on class-level attributes to define the routes it will serve. The docs show how to do this dynamically. In your case, you could do something like this:
class Server(object):
pass
for k, v in services:
setattr(Server, k, v)
Note that the setattr has to be done outside the class definition itself, as the Server name doesn't exist inside the class body.