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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def register_route(self, route_rules, label=None):
 """Registers a routing rule. :param RouteRule|list[RouteRule] route_rules: :param str|unicode label: Label to mark the given set of rules. This can be used in conjunction with ``do_goto`` rule action. * http://uwsgi.readthedocs.io/en/latest/InternalRouting.html#goto """

        route_rules = listify(route_rules)

        if route_rules and label:
            self._set(route_rules[0].command_label, label, multi=True)

        for route_rules in route_rules:
            self._set(route_rules.command, route_rules.value, multi=True)

        return self._section