Pythonic Abstract Base Class / Interface

[Michael Hudson]

Tom Evans <tom_evans_a at uk.co.yahoo.reverse> writes:

> My basic question:
> If I have a specific interface which I know is going to be implemented 
> by a number of classes, but there is no implementation commonality 
> between them, what is the preferred form for this in Python?
[...]
> So, as I see it I could:
> a) create a base class with stubs for all the interface and derive from that.
> b) create an empty base class and derive from that.
> c) just make the concrete classes directly with no inheritance commonality.
> 
> Is there a clear pythonic way, or does it depend a bit more on the 
> design of the specific program?

I'd say c) was probably the most pythonic, but it depends a bit.  a)
might have some documentation value -- for instance, you could
document required relations between the methods in their docstrings.

Cheers,
mwh

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