code: def removeslash(
      method: Callable[..., Optional[Awaitable[None]]]
  ) -> Callable[..., Optional[Awaitable[None]]]:
      
  
      @functools.wraps(method)
      def wrapper(  # type: ignore
          self: RequestHandler, *args, **kwargs
      ) -> Optional[Awaitable[None]]:
          if self.request.path.endswith("/"):
              if self.request.method in ("GET", "HEAD"):
                  uri = self.request.path.rstrip("/")
                  if uri:  # don't try to redirect '/' to ''
                      if self.request.query:
                          uri += "?" + self.request.query
                      self.redirect(uri, permanent=True)
                      return None
              else:
                  raise HTTPError(404)
          return method(self, *args, **kwargs)
  
      return wrapper
docs: Use this decorator to remove trailing slashes from the request path.
  
      For example, a request to ``/foo/`` would redirect to ``/foo`` with this
      decorator. Your request handler mapping should use a regular expression
      like ``r'/foo/*'`` in conjunction with using the decorator.