code: def sort_by(self, attr_name, reverse=False):
          
          try:
              d = dict()
              for abspath, winfile in self.files.items():
                  d[abspath] = getattr(winfile, attr_name)
              self.order = [item[0] for item in sorted(
                  list(d.items()), key=lambda t: t[1], reverse = reverse)]
          except AttributeError:
              raise ValueError("valid sortable attributes are: "
                               "abspath, dirname, basename, fname, ext, "
                               "size_on_disk, atime, ctime, mtime;")
docs: Sort files by one of it's attributes.
          
          **中文文档**
          
          对容器内的WinFile根据其某一个属性升序或者降序排序。