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pandas python

Pandas replacing values on specific columns

I am aware of these two similar questions:

Pandas replace values

Pandas: Replacing column values in dataframe

I used a different approach for substituting values from which I think it should be the cleanest one. But it does not work. I know how to work around it, but I would like to understand why it does not work:

In [108]: df=pd.DataFrame([[1, 2, 8],[3, 4, 8], [5, 1, 8]], columns=['A', 'B', 'C']) 
In [109]: df
Out[109]:
A B C
0 1 2 8
1 3 4 8
2 5 1 8
In [110]: df.loc[:, ['A', 'B']].replace([1, 3, 2], [3, 6, 7], inplace=True)
In [111]: df
Out[111]:
A B C
0 1 2 8
1 3 4 8
2 5 1 8
In [112]: df.loc[:, 'A'].replace([1, 3, 2], [3, 6, 7], inplace=True)
In [113]: df
Out[113]:
A B C
0 3 2 8
1 6 4 8
2 5 1 8

If I slice only one column In [112] it works different to slicing several columns In [110]. As I understand the .loc method it returns a view and not a copy. In my logic this means that making an inplace change on the slice should change the whole DataFrame. This is what happens at line In [110].