[Python-3000] Builtin iterator type

[Fredrik Lundh]

Greg Ewing wrote:

> If there were a substantial number of commonly
> used operations on them that could be implemented
> efficiently in a generic way, then we probably
> would have listtools and dicttools modules
> (or more properly sequencetools and mappingtools).
> That doesn't seem to have happened, though.

oh, of course it has happened.  Python's full of sequence tools, and 
there are plenty of generic operations that can work on arbitrary mappings.

and the *very* *first* *statement* a Python newcomer learns is a generic 
operation on a file-like object.

</F>