Python或Pandas使用一个键作为列表进行外部连接或合并

import pandas as pd

# 创建两个数据集
df1 = pd.DataFrame({'key': ['A', 'B', 'C', 'D'],
                    'value1': [1, 2, 3, 4]})
df2 = pd.DataFrame({'key': ['B', 'D', 'E', 'F'],
                    'value2': [5, 6, 7, 8]})

# 使用键 'key' 进行外部连接
merged_df = pd.merge(df1, df2, on='key', how='outer')

print(merged_df)

  key  value1  value2
0   A     1.0     NaN
1   B     2.0     5.0
2   C     3.0     NaN
3   D     4.0     6.0
4   E     NaN     7.0
5   F     NaN     8.0