Jack Kamm <jackkamm@gmail.com> writes:

> Hi Christopher,
>
>> This might need to mentioned in Org manual and in ob-python.el source
>> code with comment. WDYT?
>
> The main documentation for this is in the Worg page for ob-python, in
> particular see the section "Return values":
>
> https://orgmode.org/worg/org-contrib/babel/languages/ob-doc-python.html
>
> I think that is the appropriate place to put this sort of documentation
> (i.e. usage of specific babel languages). However, the clarity of this
> documentation could be improved; contributions on that would be very
> welcome.
>
> In addition, this is also mentioned in the Org manual on return values
> in Org babel, "Results of Evaluation":
>
>     For languages like Python, an explicit ‘return’ statement is
>     mandatory when using ‘:results value’.

I see, thanks. problem solved.

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