[Zope3-dev] rename 'DuplicationError'

[Steve Alexander]

In src/zope/app/content/folder.py, line 90, if you try to call setObject 
on a folder with a name that is already present in the folder, you get a 
DuplicationError.

I think this error is poorly named. A 'DuplicationError' sounds to me 
like an error to do with trying to xerox something.

I propose that this error is renamed to 'DuplicateNameError' or 
'DuplicateKeyError'.

Also, it derives from ZopeError. This feels more like a KeyError to me, 
so I think it should derive from ZopeError and KeyError.

--
Steve Alexander