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But, what is hurting my poor little neurone is the fact that I don't understand why I get the correct result when the evaluation returns a single value and a wrong answer with a table.
that's not the case. One from returns a, the other b, which are bound differently. The tuple fails with Python2 that way.
I think I have to understand how org-babel builds a table from a Python list of lists but I have to confess that I'm afraid of reading Lisp programs, though Emacs is my best friend ;)... Well, I'll keep on investigating on that subject Thanks again for your help! Roland.