Bearing in mind, four will get into dope (5)
I believe the answer is:
given
'bearing in mind' is the definition.
('given' can mean remembering or bearing in mind)
'four will get into dope' is the wordplay.
'four' becomes 'iv' (roman numeral).
'will get into' indicates putting letters inside.
'dope' becomes 'gen' (I've seen this in other clues).
'iv' going within 'gen' is 'GIVEN'.
(Other definitions for given that I've seen before include "supplied" , "Taken as read" , "Handed over; an 18 dn" , "Known fact" , "Awarded" .)