Amoeba RPC operations always need a capability parameter (this is what the `*' in the AIL function templates stands for); the service is identified by the port field of the capability. In C, the capability must always be the first parameter of the stub function, but in Python we can do better.
A Python capability is an opaque object type in its own right, which is used, for instance, as parameter to and return value from Amoeba's name server functions. Python objects can have methods, so it is convenient to make all AIL-generated stubs methods of capabilities instead of just functions. Therefore, instead of writing
some_stub(cap, other_parameters)as in C, Python programmers can write
cap.some_stub(other_parameters)This is better because it reduces name conflicts: in Python, no confusion is possible between a stub and a local or global variable or user-defined function with the same name.