I have a Pandas dataframe that looks like this
>> pd.DataFrame({'A': [1,2,3], 'B':[4,5,6], 'C':[7,8,9]})
A B C
0 1 4 7
1 2 5 8
2 3 6 9
I want to select values 1,6,8 that correspond to index-column pairs (0,'A'),(2,'B'),(1,'C'). How do I simultaneously select them?