5), at least one of our sister circuits has held that the ex post facto clause does not apply tq. the now-advisory guidelines. See United States I Demaree, 459 F.3d 791, 794 (7th Cir.2006), petition for cert. filed,No. co, 06-837 (U.S. Dec. 11, 2006); see also United States Barton, 455 F.3d 649, 65