echarts如何在环形图中间加图片

graphic: {
        elements: [
                 {
                type: 'image',
                style: {
                    image: "https://csdnimg.cn/release/blogv2/dist/pc/img/original.png",
                     85,
                    height: 80
                },
                left: 'center',
                top: 'center'
                     
                 }
        ]
    },