import pandas as pd
path=r"D:\Pyobject2023\object\Case\素材"
df=pd.read_excel(path+r"\1.01.xlsx","总表")
print(df)
df["NO"]=['NE{:02d}'.format(i) for i in range(1, len(df)+1)]
print(df)
返回：
| 姓名 | 数学 | 语文 | 英语 | |
| 0 | 小明 | 85.5 | 67 | 84.0 |
| 1 | 老张 | 89.0 | 100 | 34.0 |
| 2 | 小王 | 95.0 | 55 | 34.0 |
| 3 | 小李 | 23.0 | 95 | NaN |
| 4 | 老六 | NaN | 43 | 99.0 |
| 5 | 小王 | 100.0 | 66 | 65.0 |
| 6 | 小李 | 13.0 | 22 | 33.0 |
| 姓名 | 数学 | 语文 | 英语 | NO | |
| 0 | 小明 | 85.5 | 67 | 84.0 | NE01 |
| 1 | 老张 | 89.0 | 100 | 34.0 | NE02 |
| 2 | 小王 | 95.0 | 55 | 34.0 | NE03 |
| 3 | 小李 | 23.0 | 95 | NaN | NE04 |
| 4 | 老六 | NaN | 43 | 99.0 | NE05 |
| 5 | 小王 | 100.0 | 66 | 65.0 | NE06 |
| 6 | 小李 | 13.0 | 22 | 33.0 | NE07 |