Sorting x lists based on one list ... maybe an example would make sense:

[Peter Otten]

Philippe C. Martin wrote:

> :-) Thanks, the lists will evolve and are also stored in 'csv' format in
> external files at one point. I cannot use dictionaries because I need to
> control the sorting (hash).
> 
> In this specific case, list 1 represents students with their information,
> list 2 represents assignments with information such as weight, term, max
> grade ... and list 3 the actual grades.

This sounds like you should seriously consider using a database.

Peter