Data format issues

[zzz6666]

I want to know why y = window[-1, [0]]

The meaning of this code is to take only the first data of the last row of each window，The data I circled in the figure above
but I think all elements in the last row of each window should be taken，The data I circled in the figure below

Because the last element of each sequence should be predicted, not just the first
so i think y should be equal to window[-1]
I don’t know if my idea is correct, I look forward to your reply