Different types of dicts with letter before the curly braces.

[kindly]

I am sure people have thought of this before, but I cant find where.
I think that python should adapt a way of defining different types of
mapping functions by proceeding a letter before the curly brackets.
i.e   ordered = o{},  multidict = m{}  (like paste multidict).  So you
could define an ordered dict by newordered = o{"llvm" : "ptyhon",
"parrot" : "perl"} .  (they should also probably have there own
comprehensions as well o{foo for bar in foobar}).

People nowadays think in terms of hashes and lists (especially with
jsons and javascript not going away} and most of my time seems to be
spent in different ways to store bits of data in memory in this way.
It also seems to be the way to think in python (an object or a class
object are just mappings themselves) Most packages that I have seen re-
implement these different container types at one point anyway. It
seems a shame they are not brought up to the top level, with
potentially new, cleverer ones that have not been thought of yet.
There will be potential to add different letters to the start when it
seems that a certain mapping pattern seems in popular use.

Am I crazy to think this is a good idea?  I have not looked deeply
pythons grammer to see if it conflicts with anything, but on the
surface it looks fine.