Wow, I think I'm gonna like this forum. Thank you all for the prompt answers!
>What makes you say you "need" to know this ? Except for a couple corner >cases, you usually don't need to care about this. If you told us more >about the actual problem (instead of asking about what you think is the >solution), we might be of more help... Good point. I want to iterate recursively a dictionary whose elements might be strings or nested tuples or dictionaries and then convert values to a tagged format according to some rules. d = {'a':"i'm a", 'b':(1,2,3),'c':{'a':"i'm a",'x':"something",'y': ('a','b','c')}} I'm just designing the algorithm, but I think Python dictionaries can hold any kind of sequence? Regards, Guillermo -- http://mail.python.org/mailman/listinfo/python-list