'2x' selects current line and line beneath. Want select upwards: '2X' selects current line and line above. How to capture the number?

[thor314]

I am unsure how capture the number '2' in the keypress '2x', which selects current line and the next line.

If I were able to capture the 2, let's call this *, I could write something like this:

*X = *kj*x (since the first k moves 1 too far)

Or more literally,

*X = [ *, "move_line_up", "move_line_down", *, "extend_selection" ]