The French, one observes, are the occupiers (7)
I believe the answer is:
lessees
'the occupiers' is the definition.
The definition and answer can be both people as well as being plural nouns.
Perhaps you can see a link between them that I don't see?
'the french one observes' is the wordplay.
'the french' becomes 'les' (plural form of 'the' in French).
'one observes' becomes 'sees' (I've seen this before).
'les'+'sees'='LESSEES'
'are' acts as a link.
Can you help me to learn more?
(Other definitions for lessees that I've seen before include "People renting" , "rent payers" .)