amcharts如何隐藏图例

Question

    "graphs": [{         "valueAxis": "v1",         "lineColor": "blue",         "bullet": "round",         "bulletBorderThickness": 1,         "hideBulletsCount": 30,               "valueField": "visits", "fillAlphas": 0     }, {         "valueAxis": "v2",         "lineColor": "pink",         "bullet": "square",         "bulletBorderThickness": 1,         "hideBulletsCount": 30,         "title": "yellow line",         "valueField": "hits", "fillAlphas": 0     }],如图,删除title属性,然而还会留下一个图例,removeLegend()会删掉所有图例,求删掉底部蓝色图例.