Get Cell element in Select Cells property

[HuyNguyen7994]

I want to get the elements listed in Select Cells, but JABElement.get_cell method seems to get from Cells, which cannot be interacted with in my case.

Originally posted by @HuyNguyen7994 in https://github.com/gaozhao1989/pyjab/issues/57#issuecomment-1204637058