在Pandas中，如何按组中项目的迭代下一次出现的顺序创建列

import pandas as pd

data = {'Group': ['A', 'A', 'A', 'B', 'B', 'C', 'C'],
        'Item': ['X', 'Y', 'Z', 'X', 'Y', 'X', 'Y']}
df = pd.DataFrame(data)

df['Next_Item'] = df.groupby('Group')['Item'].shift(-1)

import pandas as pd

data = {'Group': ['A', 'A', 'A', 'B', 'B', 'C', 'C'],
        'Item': ['X', 'Y', 'Z', 'X', 'Y', 'X', 'Y']}
df = pd.DataFrame(data)

df['Next_Item'] = df.groupby('Group')['Item'].shift(-1)

print(df)

  Group Item Next_Item
0     A    X         Y
1     A    Y         Z
2     A    Z       NaN
3     B    X         Y
4     B    Y       NaN
5     C    X         Y
6     C    Y       NaN