There's got to be an easy way to do this

[Skip Montanaro]

    >> def str_join2(iters):
    >> ... elided ...

    John> The arguments to has() will be strings of unit length. The keys in
    John> the dictionary are integers.

Yeah, thanks for pointing out the error.  It does ruin the performance
advantage... ;-)

-- 
Skip Montanaro (skip at pobox.com)
(847)971-7098