在python pandas中使用下一行的Start_date填充End_date列

import pandas as pd

data = {'Start_date': ['2021-01-01', '2021-02-01', '2021-03-01'],
        'End_date': [None, None, None]}
df = pd.DataFrame(data)

df['End_date'] = df['End_date'].fillna(df['Start_date'].shift(-1))

  Start_date    End_date
0  2021-01-01  2021-02-01
1  2021-02-01  2021-03-01
2  2021-03-01        None