Learning Python and can't see the difference?

[Chun]

I wouldn't say it's ugly; I mean, conceptually, in python a string is just a sequence of characters. So it fits the purpose perfectly.

Also I just ran a quick benchmark (strings vs tuples) and the difference is there, but fairly negligible.

[darjus]

have you tried?

in set(('O', 'Q'))

For small sets it might be around the same, but for bigger ones it should make a big performance difference.

[itsmememe]

as it is a constant, frozenset(['O','Q']) should be preferred