如何找到python panda数据帧中的所有零单元并替换它们？

import pandas as pd

df = pd.DataFrame({'A': [0, 1, 2, 0], 'B': [3, 0, 5, 6]})

zero_cells = df == 0

df[zero_cells] = -1

import pandas as pd

df = pd.DataFrame({'A': [0, 1, 2, 0], 'B': [3, 0, 5, 6]})

zero_cells = df == 0
df[zero_cells] = -1

print(df)

   A  B
0 -1  3
1  1 -1
2  2  5
3 -1  6