def sort_classes(timetable, classes)
      classes.each do |c|
        if !(cmodule = timetable.module_for_code(c.code))
          cmodule = Tableau::Module.new(c.code)
          timetable.push_module(cmodule)
        end

        cmodule.add_class(c)
      end
    end
def sort_classes(timetable, classes)
      classes.each do |c|
        if !(cmodule = timetable.module_for_code(c.code))
          cmodule = Tableau::Module.new(c.code)
          timetable.push_module(cmodule)
        end

        cmodule.add_class(c)
      end
    end
Sort all the parsed classes into modules