configure.py assumes "python" command exists

[Jean-Marc Lasgouttes]

Le 27/12/2021 à 20:30, José Abílio Matos a écrit :
> Regarding the problem at hand, as an example, my suggestion is to change:
> \converter pdf4   pdf8  "python $$s/scripts/convert_pdf.py $$i $$o ebook"
> to
> \converter pdf4   pdf8  "$${python} $$s/scripts/convert_pdf.py $$i $$o 
> ebook"
> 
> The idea is to use the converter code, e.g. the $$i $$o ..., and add 
> there the substitution from $${python} to the python path that we have 
> already determined in os::find_python.

Looks good to me.

JMarc