我有一个示例数据集:importpandasaspddf={'rank1':[1,2,3,4,5,6,7,8],'rank12':[1,2,3,4,8,9,37,15],'rank13':[1,2,3,4,12,6,24,14],'N':['','','','','','','',''],'code#':[1945,13060,610,402,1067,180,411,93],'score1':[100,97,95,92,87,85,80,79],'score2':['yes','yes','no','no','yes','yes','no','yes'],'score3':[10,9,10,