@Alex Mashin: you added a link to Extension:External Data/Local_programs#Complex_example, but it doeesn't look like that's very related to Diagrams. Also, the section ID doesn't exist.
Topic on Extension talk:Diagrams
I have updated the section title. It contains information about External Data use case that allows to draw diagrams.
Alexander Mashin talk 02:37, 18 June 2022 (UTC)
Great, thanks!