Set MyRange= Range(ap). How to write in Open Office Basic

So I have been converting a Code from VBA to OpenOffice (BASIC) and came with an apparently simple problem which I have been dealing with for hours without an answer.

How do I get a Range (Ex: "A2:A4") in OpenOffice BASIC from a Input cell in which exactly "A2:A4" is written?

The code in VBA is very simple

ap = Cells(1, 2)

Set MyRange = Range(ap)

OBS: The string in ap (Ex:"A2:A4") comes from another function.

Thanks a lot in advance.