如何用零填充pandas数据帧中的缺失值？

import pandas as pd

# 创建一个包含缺失值的数据帧
df = pd.DataFrame({'A': [1, 2, None, 4, 5],
                   'B': [None, 6, 7, 8, None],
                   'C': [9, 10, 11, None, 12]})

# 用零填充缺失值
df_filled = df.fillna(0)

print(df_filled)

     A    B     C
0  1.0  0.0   9.0
1  2.0  6.0  10.0
2  0.0  7.0  11.0
3  4.0  8.0   0.0
4  5.0  0.0  12.0