code: def has_root_router(self):
          
          try:
              mw = self.middleware.last()
          except IndexError:
              return False
  
          return (
              isinstance(mw.func, Router)
              and mw.mask == HTTPMethod.ALL
              and mw.path is MiddlewareChain.ROOT_PATTERN
          )
docs: Returns true if the bottom middleware of the chain is an
          instance of growler.Router, the mask matches ALL methods, and
          the path is the root (/) path.
  
          Returns:
              bool: Whether the last element in chain is a "root router"