pandas 操作excel中的行转列

行转列：

https://blog.csdn.net/Eric_data/article/details/104645738

https://www.cnblogs.com/traditional/p/11967360.html

透视图：

https://www.cnblogs.com/onemorepoint/p/8425300.html

https://www.jianshu.com/p/9ded1c198123