code: def _require_auth(fnc):
      
      @wraps(fnc)
      @_assure_identity
      def _wrapped(*args, **kwargs):
          if not identity.authenticated:
              msg = "Authentication required before calling '%s'." % fnc.__name__
              raise exc.NotAuthenticated(msg)
          return fnc(*args, **kwargs)
      return _wrapped
docs: Authentication decorator.