In France, one is where courses take a long time to get through (4)
I believe the answer is:
unis
'courses take a long time to get through' is the definition.
I don't know anything about this answer so I cannot judge whether this works.
'in france one is' is the wordplay.
'in france' becomes 'un' (I've seen this in other clues).
'un'+'is'='UNIS'
'where' is the link.
(Other definitions for unis that I've seen before include "Places of education" , "seats of learning" .)