[ setoid_rewrite (iso_comp1 i1) | setoid_rewrite (iso_comp2 i2) ];
reflexivity.
Defined.
+Notation "a >>≅>> b" := (iso_comp a b).
Definition functors_preserve_isos `{C1:Category}`{C2:Category}{Fo}(F:Functor C1 C2 Fo){a b:C1}(i:Isomorphic a b)
: Isomorphic (F a) (F b).