reserve A,B,C for Category,
  F,F1 for Functor of A,B;
reserve o,m for set;
reserve t for natural_transformation of F,F1;

theorem
  Functors(A,[:B,C:]) ~= [:Functors(A,B),Functors(A,C):]
proof
  take distribute(A,B,C);
  thus thesis;
end;
