How to change the arrow style of a LEADER?

[luoyu-123]

Hello, respected Mr. Mozman, I want to change the arrow style when using the add_leader() interface function, but no matter how I pass in the override parameter ('dimblk','dimblk1','dimblk2') these three None of the results obtained by the attributes took effect.
It turns out that the arrow style cannot be changed：
，
I want to get the style of the arrow：

[mozman]

You have to override the dimvar dimldrblk.