Accomplished poet, we're told (4)
I believe the answer is:
done
'accomplished' is the definition.
(to do something is to accomplish it)
'poet we're told' is the wordplay.
'poet' becomes 'Donne' (16th- and 17th- century poet John Donne).
'we're told' shows a homophone (sound like).
'donne' sounds like 'DONE'.
(Other definitions for done that I've seen before include "Tricked" , "See 23" , "that may be said to seal a deal" , "Achieved" , "(Of food) well cooked" .)