如何在pandas中使用lead in days添加标识符列？

import pandas as pd

df = pd.DataFrame({'date': ['2022-01-01', '2022-01-02', '2022-01-03', '2022-01-04'],
                   'value': [10, 20, 30, 40]})

df['next_value'] = df['value'].shift(-1)

import pandas as pd

df = pd.DataFrame({'date': ['2022-01-01', '2022-01-02', '2022-01-03', '2022-01-04'],
                   'value': [10, 20, 30, 40]})

df['next_value'] = df['value'].shift(-1)

print(df)

         date  value  next_value
0  2022-01-01     10        20.0
1  2022-01-02     20        30.0
2  2022-01-03     30        40.0
3  2022-01-04     40         NaN