let A, B, C be Category; for F being Functor of [:A,B:],C
for a being Object of A holds (export F) . a is Functor of B,C
let F be Functor of [:A,B:],C; for a being Object of A holds (export F) . a is Functor of B,C
let a be Object of A; (export F) . a is Functor of B,C
(export F) . a = F ?- a
by Th24;
hence
(export F) . a is Functor of B,C
; verum