def get_spider_stats(self, spider_name):
        """get-spider-stats <spider> - get stats of a running spider"""
        if spider_name is None:
            spider_name = self.spider_name
        else:
            self.spider_name = spider_name
        if self.spider_name is None:
            self.spider_name = self.list_running()[0].split(':')[-1]
        return(self.jsonrpc_call('stats', 'get_stats', self.spider_name))