背景
我这里有一个被分片存储的 csv 文件,如下所示 | time| A | B | C | D| | ---- | -- | - | -- | -- | | 20:00|0| 1| 2| 3| | time| E | F | G | H| | 20:00|4|5|6|7|| ... 现在想读成 | time| A | B | C | D| E | F | G | H| | --- | --- | --- | --- | --- | --- | --- | --- | --- | | 20:00|0|1|2|3|4|5|6|7|