PEP 245: Python interfaces

[Clark C. Evans]

On Sat, 31 Mar 2001, Scottie wrote:
> The one further thing I'd like to see is a way to declare that a class
> implements an interface without having to edit either the interface
> or the class -- Imagine the situation where I obtain two packages,
> and I want to tell the one package that it can accept objects from
> the other.

This is very similar to what PEP 246 is attempting to address.
It covers "bi-directional" case.  The case you mention is more
of a third party registry, it is addressed in case "e" of the PEP,
and could be added later if necessary.

Clark